Collective Memory as Tool for Intergroup Conflict: The Case of 9/11 Commemoration

We apply a cultural psychology approach to collective memory of the 9/11 terrorist attacks. In particular, we considered whether practices associated with commemoration of the 9/11 terrorist attacks would promote vigilance (prospective affordance hypothesis) and misattribution of responsibility for the original 9/11 attacks (reconstructive memory hypothesis) in an ostensibly unrelated context of intergroup conflict during September 2015. In Study 1, vigilance toward Iran and misattribution of responsibility for the 9/11 attacks to Iranian sources was greater among participants whom we asked about engagement with 9/11 commemoration than among participants whom we asked about engagement with Labor Day observations. Results of Study 2 suggested that patterns of greater vigilance and misattribution as a function of instructions to recall engagement with 9/11 commemoration were more specifically true only of participants who reported actual engagement with hegemonic commemoration practices. From a cultural psychological perspective, 9/11 commemoration is a case of collective memory not merely because it implicates collective-level (versus personal) identities, but instead because it emphasizes mediation of motivation and action via engagement with commemoration practices and other cultural tools.


Background
The attacks of September 11, 2001 took the lives of almost 3,000 civilians.The events were immediately and simultaneously tragic and rife with political repercussions, and thus each year the event is commemorated.

Why was this study done?
We were interested in assessing how commemorations of 9/11 evolve over time, and to understand how the meaning of the memory is called upon to inform discussion of ongoing political issues.For example, exactly one year after the attacks, then-U.S. president George W. Bush spoke to the U.N. about the threat of Iraq attaining weapons of mass destruction by harkening to the attacks of 9/11.In the same way, almost 15 years later, politicians continue to invoke 9/11 in attempts to warn the public about the threat of future terrorist attacks.How does such rhetoric shape commemorations meant to honor the innocent victims of the attacks-could it be that commonplace commemorations among citizens can trigger hawkish foreign policy attitudes in the same way we saw in the immediate aftermath of the attacks?

What did the researchers do and find?
We conducted two experiments that compared how attitudes towards a present-day foreign policy issue-Iran's nuclear program-are related to commemorations of 9/11 (compared to Labor Day commemorations or no commemoration).
"With every step the Iraqi regime takes toward gaining and deploying the most terrible weapons, our own options to confront that regime will narrow.And if an emboldened regime were to supply these weapons to terrorist allies, then the attacks of September the 11th would be a prelude to far greater horrors."George W. Bush, Address to the United Nations, September 11, 2002.On the morning of September 11, 2001, hijackers crashed two planes into the North and South Towers of the World Trade Center in New York City and one plane into the Pentagon in Washington DC.A fourth plane crashed in an empty field in rural Pennsylvania after passengers resisted the hijackers and thwarted another attack.Both towers of the World Trade Center eventually imploded and collapsed, leaving a death toll of almost 3,000 in the worst terrorist attack in U.S. history.
On the one-year anniversary of these "9/11" terrorist attacks, U.S. President George W. Bush traveled to New York to participate in commemoration ceremonies.While in New York, he addressed the United Nations to win support for a plan to invade Iraq.His address is noteworthy not only as a case of the topic of this special section (i.e., the use of collective memory as a tool for intergroup conflict), but also as an illustration of the reconstructive character of collective memory.Although all available evidence suggests that the government of Saddam Hussein played no active role in the 9/11 attacks (including support for the al-Qaeda perpetrators; Center for Public Integrity, 2008), then-President Bush created an ecological association by juxtaposing "the Iraqi regime" and "the attacks of September the 11th" in the context of his address.Frequent repetition of this association by members of the Bush regime may be one reason that many U.S. respondents reported a mistaken belief-a sort of false collective memory-about the connection between Saddam Hussein and the 9/11 attacks (Pew Research Center, 2002).
Each September 11 since 2001, communities across the U.S. have continued to perform a variety of commemoration practices.In many communities, sirens blare or bells toll to mark the exact times that the planes crashed into the towers (e.g.Ma, 2009;Muskal & Susman, 2013).Many schools dedicate a moment of silence on the morning of each September 11, and the National September 11 Memorial Museum in New York offers lesson plans that teachers can use in classrooms to educate students about the events.Beyond sirens and moments of silence, sporting events that fall on September 11 often include some form of symbolic remembrance.The National Football League (NFL), host of the most watched broadcasts on U.S. television, typically requires coaches and players to display helmet decals or other visible symbols of 9/11 on their uniforms for any games that fall on September 11.For the fifteenth anniversary of the 9/11 attacks in 2016, NFL stadiums displayed video messages from former and current U.S. Presidents George W. Bush and Barack Obama to remember the victims and first responders.As these examples illustrate, many people encounter commemoration activities not through some deliberate personal intention to participate, but instead in the context of otherwise unrelated events or in the flow of everyday life.
These and other cultural practices of 9/11 commemoration are not simply reminders of the actual attacks, but also invite participants to reflect upon the U.S. and international response to the attacks, related events during the intervening period, and their meaning in light of current events.In many cases, the explicit or ostensible purpose of such commemoration practices is to honor the sacrifices and mourn the losses of that day.In this article, we consider another purpose of commemoration practices that was evident in the case of Bush's address.Specifically, commemoration practices often serve to motivate collective action for intergroup conflict: not only vengeance against the perpetrators of the original attack or vigilance against new attacks, but also extension of the associated "war on terror" (Bush, 2001) to new cases of intergroup conflict.These include the case of Bush's address and the invasion of Iraq as well as the case that we consider in this article: the debate surrounding Iran and its nuclear program.

Collective Memory: A Cultural-Psychological Approach
The emphasis on commemoration and other practices of collective memory reflects the foundation of our work in perspectives of cultural psychology.Although approaches vary, the particular version of cultural psychology that informs the present work emphasizes the cultural-historical or ecological foundations of mind (e.g., Cole, 1995, on the idea of "mind in context") and a dynamic relationship of mutual constitution between mental structures inscribed in bodies and in the materiality of everyday worlds (Adams, Salter, Pickett, Kurtiş, & Phillips, 2010).In one direction of this relationship (i.e., the sociocultural constitution of psychological experience), species-typical human development is not the just-natural expression of a genetic blueprint; instead, it requires engagement with particular mentalities embedded in "already-there" (Shweder, 1990) cultural worlds.In the other direction of this relationship (i.e., the psychological constitution of cultural worlds), the everyday ecology of human experience is not a just-natural environment; instead, species-typical human beings inhabit cultural worlds that are a product of human design, with features that come to be "already there" through prior human activity.Accordingly, cultural psychology perspectives approach the study of collective memory as a case of "mind in context" (Adams et al., 2010).This approach shifts the focus of investigation beyond personal recollections of the collective past to a process of collective remembering mediated by cultural tools (see Wertsch, 2002).
Much work on collective memory within social and political psychology bears the influence of social identity theory (Tajfel & Turner, 1986) and self-categorization theory (Turner, Hogg, Oakes, Reicher, & Wetherell, 1987), which posit a distinction between psychological processes operating at individual (or personal) and collective (or social) levels of self/identity.From this perspective, both individual and collective processes (e.g., memory, emotion, and motivation) are manifestations of individual experience, but differ according to whether personal or social identity is salient in a situation.A cultural psychology perspective extends the notion of collective beyond individual experience to consider the extent to which psychological processes are mediated through material or ecological manifestations of mind.One well-known example of this idea concerns the "imagined community" (Anderson, 1983) of national and other collective identities.Observers propose that this sense of community is difficult to accomplish in the abstract, and instead requires corresponding ecological manifestations or cultural tools (e.g., print media, flags, monuments, memorials to unknown soldiers, and master narratives inscribed in history texts) that make the collective identity easier to imagine (Anderson, 1983;Hammack, 2011).With respect to the topic of memory, this approach emphasizes that understandings of the past are not the sole property of atomized individual minds, but develop through engagement with commemoration practices, cultural products, and other cultural tools for memory.These tools include relatively explicit forms such as university entrance exams (Kurtiş, Soylu Yalcinkaya, & Adams, 2017, this section), museum exhibits (Mukherjee, Salter, & Molina, 2015), monuments (Licata & Klein, 2010), and classroom displays (Salter & Adams, 2016).They also include relatively implicit forms such as the ecological association between "the Iraqi regime" and the "attacks of September the 11th" that Bush (2002) created or reproduced in his address to the U.N.
Related to this emphasis on material manifestations of mind is an appreciation for the intentionality of everyday worlds (Salter & Adams, 2016; see Shweder, 1990).On one hand, the reference to intentionality highlights the directed character of cultural worlds.Humans do not inhabit a neutral or indifferent nature, but instead inherit cultural worlds invested with a psychological charge over iterations of activity as people selectively (re)produce features that resonate with their beliefs and desires about what is true and good.On the other hand, the reference to intentionality highlights the directive character of cultural worlds.Cultural practices and products carry their psychological charge to exert influence on new generations of (sometimes unwitting) actors beyond the original context of their creation.From this perspective, the collective character of the memory process refers not simply to the storage and distribution of information across individual actors, but more importantly to the extent to which cultural tools for collective memory mediate social influence and motivational force to new contexts of collective activity.
To illustrate this point, consider the issue of intentionality and motivation with respect to commemoration.Again, the pervasiveness of 9/11 commemoration means that one encounters and engages in commemoration practices regardless of one's personal motivation or intention to do so.Like it or not, one encounters invitations to commemorate as sirens blare during the commute to work; as teachers or supervisors enact moments of silence; as public service announcements interrupt regular broadcasts to recall the 9/11 attacks; or in myriad other impositions of 9/11 commemoration practice.Implicit in these commemoration practices is a psychological charge that resonates with the beliefs and desires of previous actors: for example, a sense of anger associated with a desire for vengeance or a sense of anxiety associated with a desire for vigilance.As people engage with these commemoration practices, this psychological charge exerts its influence through processes related to the automaticity of everyday life (Bargh & Chartrand, 1999), affording responses and action that may be at odds with a person's explicit beliefs or higher intentions.In many cases of hegemonic commemoration where the collective motivation is conscious or explicit, a person may be able to effectively resist the directive force associated with the practice.In many other cases where the collective motivation is less explicit, people are likely to attune their responses to the affordances or directive force inherent in the commemoration practice.In such cases, one can say that the person becomes the agent who acts on behalf of the collective motivation or "moral good" implicit in the commemoration practice (see Shweder, Jensen, & Goldstein, 1995).

Memory and Identity
Chief among the moral goods or motivations inherent in national commemoration practices are beliefs and desires about national identity.An abundance of research dating at least from William James (1890) has described the bi-directional relationship between memory and identity.In one direction, people draw upon past personal experience to construct and maintain a coherent sense of self (Pasupathi, 2001).In the other direction, people's current selfviews can reciprocally mold the memory of past experience to cohere with present beliefs and goals (Wilson & Ross, 2003).Although most of the research has considered the bidirectional relationship between autobiographical memory and personal identity, social and political psychologists have extended the focus to consider the bidirectional relationship between collective memory and social identity.In one direction, people draw upon understandings of the collective past to construct a sense of collective identity: an experience of imagined community (Anderson, 1983) with people who are otherwise distant in time and space.
Collective memory affords identity stories or coherent narratives that provide both a sense of continuity across a disjointed collective past and a sense of direction that points beyond the present and projects into the collective future (McAdams, 2001).Commemorations and other cultural representations of the national past constitute tools that not only afford definitions of who the national "we" are, but also afford a sense of who "we" might become (i.e., possible national selves).Understandings about the collective past that emphasize collective wrongdoing can afford national disidentification and an experience of collective guilt that can motivate reparation (Brown, González, Zagefka, Manzi, & Čehajić, 2008; see Wohl, Branscombe, & Klar, 2006 for a review).Closer to the concerns of this paper, commemorations that emphasize indignation about collective victimization can afford identification with belligerent constructions of the nation and a sense of collective anger that can dampen collective guilt in the face of ongoing ingroup transgressions (Wohl & Branscombe, 2008) or motivate retribution against the perpetrators (Cheung-Blunden & Blunden, 2008;Skitka, Bauman, Aramovich, & Morgan, 2006;Young, 2003).
In the other direction, people re-member-in the sense of both recall and reconstruct-the collective past in ways that resonate with their current beliefs and desires (e.g., Klein, Licata, & Pierucci, 2011;Sahdra & Ross, 2007).
Commemoration events afford people the opportunity to act on the motivations for positive social identity and to remember the collective past in nation-glorifying or otherwise identity-enhancing ways: not only emphasizing collective triumphs, but also silencing collective failures through both outright omission and minimization of relevance for current events (Kurtiş, Adams, & Yellow Bird, 2010;Sahdra & Ross, 2007).Moreover, given the extent to which collective memory narratives project into the future and direct collective action (e.g., Hammack, 2011), people may use the opportunity of commemoration to remember a useful past that provides justification for current political projects.In the case of the present research, this suggests that 9/11 commemoration may afford people the opportunity to remember the past in ways that reflect current intergroup relations.
In sum, commemorations are not simply an occasion to remind people about the past events upon which they are based.Instead, each instance of commemoration provides an opportunity to collectively reconstruct the meaning of past events in ways that resonate with present-day identity concerns, including new cases of intergroup conflict.In turn, these collective reconstructions provide an opportunity to direct motivations for belligerence and vigilance beyond original perpetrators to new outgroup targets who are otherwise unrelated to the source of collective victimization.

The Present Research
The present research considers these ideas in the context of two experiments that we conducted shortly after the The work builds on a foundation of previous research, which has examined the consequences of the 9/11 attacks or subsequent reminders for social psychological experience (Crowson, Debacker, & Thoma, 2006;Davies, Steele, & Markus, 2008;Huddy & Feldman, 2011;Li & Brewer, 2004).Research suggests that high-intensity exposure to the attacks resulted in a general conservative shift and a desire for revenge among a sample of New Yorkers, regardless of the survivor's political ideology (Bonanno & Jost, 2006).More generally, results of a three-wave study with undergraduates before and after the 9/11 attacks indicated that positive attitudes towards war were greater on September, 20, 2001 compared to one year prior, although these attitudes returned to baseline within one year (Carnagey & Anderson, 2007).Such consequences are not limited to the original experience of 9/11 events, but also can follow from reminders of the 9/11 attacks long after they occurred.One relevant study demonstrated that reminders of 9/11 increased preferences of U.S. participants for bellicose foreign policy (specifically, military intervention in Syria) relative to either reminders of the 2005 London bombings or no reminder (Washburn & Skitka, 2015).These are only a few illustrative examples of an impressive body of research that has demonstrated how experience and reminders of the 9/11 attacks have had important implications for outcomes related to intergroup relations.The current work extends this research in two important ways.
First, previous research has focused attention on experience of or threatening reminders about the 9/11 attacks, per se.In one illustrative case, researchers primed participants with passages stating that on "the morning of September 11, 2001, 19 terrorists…hijacked four commercial airplanes, deliberately crashing two of the planes…The attacks killed many people and injured even more" (Washburn & Skitka, 2015).In another case, researchers directed participants to "write down as specifically as you can what happened during the terrorist attacks on September 11, 2001" (Landau et al., 2004).In contrast, the present work extends research beyond (reminders about) 9/11 events to consider consequences associated with (reminders about) engagement in hegemonic practices of 9/11 commemoration.
ii Although reminders about engagement in hegemonic 9/11 commemoration practices are likely to remind people about the original attacks, they also do much more.Especially as years pass and society fills with people who do not have direct experiential memory of September 11, 2001, reminders about engagement make salient the collectively constructed meanings attached to commemoration practices in the intervening period (including of the ongoing trail of responses that continue to unfold in the present).Implicit in this extension is the idea that exposure to reminders about 9/11 does not happen by random assignment to condition.
Instead, people encounter reminders in the context of already-there intentional worlds that have evolved or are designed to afford particular constructions of the 9/11 attacks that carry collective motivation for direction of ongoing intergroup relations.
Second, the current studies extend consideration of consequences for intergroup relations to a new target unrelated to the original event.Specifically, we examined the impact of commemoration salience on beliefs about the Joint Comprehensive Plan of Action (JCPA), commonly referred to in the U.S. as the "Iran nuclear deal.At first glance, our selection of the JCPA as a case of intergroup relations may seem strange.If one imagines that the effect of 9/11 commemoration is to motivate conflict toward relevant perpetrators, then there would be little reason to expect that commemoration would impact outcomes related to a target, Iran, that had no role in the 9/11 attacks.Accordingly, we did not select this case of intergroup relations because of any inherent connection to the original events.Instead, we did so in anticipation of the possibility that-as Bush did in his address at the U.N. on the first anniversary of the 9/11 attacks-political actors might use the affordance of 9/11 commemoration and associated calls for vigilance to reconstruct memory of the 9/11 attacks in ways that imply greater responsibility of Iranian actors and promote suspicion about the JCPA in the service of more belligerent U.S. action. iii The design of the both studies permitted the test of two hypotheses.A first, prospective affordance hypothesis concerns the implications of hegemonic 9/11 commemoration for ongoing intergroup relations.Specifically, this hypothesis (H1) suggests that suspicion about Iran and the JCPA will be greater among participants for whom engagement with hegemonic 9/11 commemoration practices is salient than among participants in comparison conditions for whom such engagement is not salient.A second, reconstructive memory hypothesis concerns the implications of hegemonic 9/11 commemoration for beliefs about historical events.Specifically, this hypothesis (H2) suggests that (false) attributions of responsibility for the 9/11 attacks to Iranian actors will be greater among participants for whom engagement with 9/11 commemoration practices is salient than among participants in comparison conditions for whom such engagement is not salient.

Procedure
We randomly assigned participants to one of two conditions.In the 9/11 condition, we instructed participants to describe what (if anything) they did on Friday, September 11, 2015 to commemorate the 9/11 attacks.Participants responded to the following prompt: "We have learned that some people commemorate the events of 9/11/2001 and some people do not.Briefly describe your life on that day (Friday, September 11, 2015).Did you do anything special-that is, apart from your daily routine-related to commemoration of the 9/11 attacks?"In the Labor Day condition, we used the same prompt to instruct participants to recall their experiences on the Labor Day holiday that U.S. residents marked on Monday, September 7, 2015.
Besides constituting the experimental manipulation, responses to the open-ended item also provided an important opportunity for insight about people's engagement with 9/11 commemoration practices.Of particular interest was whether engagement with 9/11 commemoration practices resulted from a deliberate decision to do so.To the extent that engagement was instead a coincidental byproduct of action for some other purpose, one can understand effects of commemoration as the product of collective intention mediated through cultural practices rather than individual intention.

National Identification
Participants used a scale from 1 (strongly disagree) to 7 (strongly agree) to rate the extent to which they agreed with four items that we adapted from a measure of collective identification (Cameron, 2004).Two items tapped national identity centrality: "In general, the fact that I am an American is an important part of my self-image" and "I often think about the fact that I am an American."The other two items tapped ingroup affect: "In general, I'm glad to be a citizen of the United States" and "I feel good about being an American," α = .88.

Demographics
Finally, participants indicated their age, gender, racial category identification, and political orientation (an average of two items separately measuring economic and social political orientations, 1 = very liberal, 7 = very conservative).

Results
Responses to the open-ended item about 9/11 commemoration reveal different ways that people engaged with practices of collective memory (Table 1).• We had a high school football game to attend.We participated in a moment of silence before the game.
• I didn't have to work!Slept all day and got paid for it.
• I did.I went to our neighborhood pool where we have grills and I grilled a ton of chicken and beef and drank beer all day long to celebrate my labor.
• This year, I did not do anything that day.I did everything as I normally would besides watching the movies based on the Sept 11 attacks.

• •
We took a short vacation over the weekend.
No i just shared things on my Facebook about it.

• •
When I put my Flag out in the morning I made sure it was at Half staff.And that was about it and I reflected where I was on that day I did attend a barbeque with neighbors which was nice and Presidential politics were discussed.Other than that it was routine.
• I said a prayer and attended a memorial.• I went to a family barbecue.I talked to family and friends who were invited.Other than that, I did nothing else special that day.
• I did not do anything special.I did have a couple of brief discussions about the victims and the war on terror.• I drank during the day, which was a nice change of pace.But I basically saw it as a three-day weekend and treated it like it was just another day.
• I live on a key and the main drag on this long island has been lined every year since 9/11/2001 with American flags, each representing a life lost due to the attacks that day.I walked with my dog along the road quite a ways and said some silent prayers.
• On Labor Day, I gathered with my family for a picnic.Rather than celebrate the true meaning of Labor Day, it was used to celebrate the unofficial end of Summar (sic).We dined outside on our deck and bonded as a family.
• I joined in on a moment of silent at my son's school on that morning.I also gave some thought throughout the day about the individuals lost, the families still suffering, and where I was on the day 14 years ago.
• I went shopping with my Mom on Labor Day and took advantage of the big sales.
• I went to my job in a school and the rest of my day was normal except in school, the entire school sang the national anthem at 1:00.
• I did not do anything special on Labor day other than display an American flag on my front porch.
• There was a company dinner in which donations were made to the NYC Fire Dept.out of respect for the fallen on 9/11.
In some cases, participants reported conscious or intentional decisions to engage in relatively private or personal (but still very social or collective) forms of commemoration practice (e.g., "When I put my flag out in the morning I made sure it was at half-staff").In other cases, participants reported conscious or intentional decisions to engage in relatively public or collaborative forms of commemoration practice (e.g., "I … attended a memorial").Most interesting for current purposes, participants also reported that they encountered forms of commemoration practice in the course of their everyday activity often without any mention of any personal intention or deliberate plan to do so.Examples included a moment of silence at a high school football game or during the morning routine at a child's school, a flag-lined road while walking a dog, singing the national anthem at a school-based workplace, and a company dinner where people made donations to the New York Fire Department in honor of 9/11 responders.
These examples illuminate the collaborative process of collective memory.People in the course of everyday activity encounter practices of an already-there cultural world that induce them to recall the 9/11 attacks and subsequent related events, often without any deliberate intention to participate in these practices.In turn, these practices exert directive force on people's beliefs, desires, and actions, often without their conscious awareness this influence.1, 173) = 6.83, p = .01,η p 2 = .05(see Figure 1a).There was no significant difference between the current model within a regression framework and one that included interactions between the manipulation and both national identification and political conservatism, F(4, 169) = .59,p = .67.

Discussion
Results provided evidence for hypothesized effects of the manipulation on both outcomes of interest.With respect to consequences for current intergroup relations, participants who reported their engagement with 9/11 commemoration indicated greater suspicion about Iranian intentions than did participants in the Labor Day condition.With respect to memory of the 9/11 attacks, participants who reported their engagement with 9/11 commemoration assigned greater responsibility to Iranian leaders (and to some extent actual sources, Bin Laden and the Taliban) than did participants in the Labor Day condition.
Although results are consistent with hypotheses, it remains unclear what feature of the manipulation-(mental rehearsal of) actual engagement with commemoration practices or merely the salience of the 9/11 attacks-is the active ingredient that produced the observed effects.In other words, observed effects may be another case of the well-documented pattern whereby reminders of the 9/11 attacks promote outgroup distrust and belligerent foreign policy beliefs (e.g.Landau et al., 2004;Washburn & Skitka, 2015).The fact that responsibility attribution items included mention of the 9/11 attacks casts doubt on the "mere reminder" account as an explanation for observed effects, at least for that outcome, as the 9/11 attacks were at that point salient for all participants.However, stronger support for the idea that (rehearsal of) engagement with commemoration practices was the source of observed effects (rather than reminders about the 9/11 attacks, per se) would come from evidence that engagement in commemoration practice moderated effects of the commemoration salience manipulation.We could not examine this possibility in Study 1 because we had information about engagement with 9/11 commemoration practices only for participants in one condition (9/11) and not the other (Labor Day).

Study 2
To examine this possibility in Study 2, we asked all participants to report their engagement with 2015 9/11 commemoration practices either before or after completing dependent measures.We coded responses to this item for the extent to which participants reported engagement with hegemonic practices of 9/11 collaboration.We then used these responses about collaboration to test a corollary to the primary hypotheses in the form of a moderation effect.Specifically, we considered whether hypothesized effects of the 9/11 commemoration salience manipulation-both greater suspicion and attribution of responsibility-would be more precisely evident only among participants who reported engagement with hegemonic 9/11 practices.

Method Participants
We recruited 238 participants (46.20% female; M age = 36.04years, SD age = 11.63;80.7% White/European American, 8.4% Black/African American, 4.6% Hispanic/Latino, 3.4% Asian, 2.5% mixed race, 0.4% Middle Eastern/North African; 54.7% completed at least college) from Amazon Mechanical Turk on September 30, 2015 (i.e., 19 days after commemoration events associated with the 14 th anniversary of the attacks).They received 1 USD as compensation for completion of an online survey.• No, i actually did not realize it was 9/11 until the following morning.Then i realized that that is why history channel had the show on.
• I did nothing special as i was not personally affected by 9/11.

Low commemoration 1
• I just talked to my boyfriend and my friend about that day.
• My friend and i were together on that that day, and we were together on 9/11 this year.We remembered how scary it was and what we did to stay calm.My boyfriend lived in new jersey on 9/11 an he told us about that.
• I always take time out that day to pray for those who lost their lives that day as well as for their families.
• No, I just watched some of the specials on tv and drove past our local 9/11 memorial on my way home from work.
• I didn't do anything out of the ordinary other than listen to a podcast doing a "retrospective" of 9/11/2001.

High commemoration 2
• I took my daughter, who is a member of the high school marching band, to a memorial that she was playing at.
• Posted rememberance (sic) memorabilia to social media sites and changed the profile pictures to indicate we should honor the memory of the Fallen and the families left behind.
• I changed my Facebook Pic to a picture of a half-mast flag with the two Rays of light in the background.
• I did not really do anything special.I did however go to a baseball game on Friday September 11 and we all stood and honored some victims' families from flight 93 • My husband is in the Navy, when he went to work I went with him (most of the other wives do the same) and we all had a minute of silence at colors.('colors' is the term given by military to the daily ritual of raising the flag at dawn).

Flashbulb memories
• I was a 19 year old kid sticken (sic) with disbelief as I watched a smoky skyscraper on fire.The horror only intensified when I watch an airplane slam into the building right next to it.That was truly a sad day.

Critical interpretations
• none because talking about 9/11 just brings back more memories of american (sic) allowing us to go to war • No, if I had a joint I would have smoked it, but no as stated I avoided the foul taste of the 11 September jingoism.

Suspicion About Iran and the JCPA
Independent samples t-tests showed no effect of the manipulation on either national identification or political conservatism, ts < 1.4, ps > .17.Unlike Study 1, an ANCOVA revealed no main effect of the manipulation on vigilance about the Iran nuclear deal, F(1, 235) = .94,p = .33(see Figure 1b).However, the design of Study 2 permitted us to investigate the corollary to the prospective affordance hypothesis (H1) in the form of a moderation effect: that is, whether the effect of reporting 9/11 commemoration depended on (self-reported) level of engagement with commemoration activity.To test this possibility, we conducted a multiple regression analysis that included the Condition (0 = control, 1 = 9/11 commemoration), Commemoration Engagement, and Condition X Commemoration Engagement interaction term, while controlling for national identification and political conservatism.Neither main effect was significant, ts < .7,but the Condition X Commemoration Engagement interaction was significant, b = .79,SE = .33,t(226) = 2.39, p = .02.To probe this interaction, we used online utilities (Preacher, Curran, & Bauer, 2006) to conduct simple slope analyses and estimate vigilance about Iran at each level of commemoration engagement.
Results of the probe revealed the hypothesized pattern.The manipulation had no effect on vigilance about Iran among participants who did not report any commemoration practice, b = -.17,p = .50.In contrast, the manipulation did have the hypothesized effect among participants who reported low (b = .62,SE = .29t = 2.16, p = .

Responsibility for 9/11 Attacks
We conducted a parallel set of analyses on attribution of responsibility for the 9/11 attacks to test the corollary to the reconstructive memory hypothesis (H2).In separate models, we entered Condition (0 = control, 1 = 9/11 commemoration), Commemoration Engagement, their interaction, political conservatism, and national identification as simultaneous predictors of the three 9/11 responsibility measures.
The model predicting attributions to Iranian sources (Khatami and Khamenei) revealed a significant Condition X Commemoration Engagement interaction, b = .70,SE = .33,p = .038,associated with the corollary to the primary hypothesis in the form of a moderation effect.A probe of the interaction revealed that results were generally consistent with the hypothesized pattern, although simple effects of the manipulation at each level of commemo-ration engagement did not reach conventional levels of statistical significance.Specifically, the hypothesized tendency to attribute greater responsibility to Iranian sources after (versus before) reporting 9/11 commemoration was evident only among participants who reported high (b = .94,SE = .56,p = .10)or low (b = .24,SE -.29, p = .41)engagement with hegemonic 9/11 commemoration.This pattern was not evident among participants who reported no engagement with hegemonic commemoration practices; instead, we observed an unexpected, negative effect of the manipulation on attributions of responsibility to Iranian sources that likewise did not reach conventional levels of statistical significance (b = -.46,SE = .25,p = .07).v Similar interactions emerged in the models predicting attributions to Bin Laden/Taliban (b = .72,SE = .27,p = .009)and Saddam Hussein (b = .88,SE = .41,p = .035).Probes of these interactions indicated similar patterns as for attributions to Iranian sources.Specifically, attribution of responsibility to all targets was greater among participants who reported engagement with hegemonic 9/11 commemoration practices when they recalled their engagement before versus after responding to dependent measures.This contrasts with results of Study 1, in which recall of 9/11 commemoration resulted in greater attributions of responsibility to only false Iranian and actual targets, but not to Saddam Hussein.We consider this slight discrepancy across studies in the General Discussion.

Discussion
Results of Study 2 qualified results of Study 1 in a theoretically meaningful way.Specifically, we observed evidence for the moderation effect associated with the corollary to the primary hypotheses.The hypothesized tendencies to indicate greater vigilance about Iran (H1) and to (mis)attribute greater responsibility for the 9/11 attacks to Iranian sources (H2) after (versus before) recalling 9/11 commemoration were evident only among participants who reported engagement with hegemonic commemoration practices.Participants who reported no engagement in hegemonic 9/11 commemoration or who responded to dependent measures before recalling their engagement with hegemonic commemoration practices reported less vigilance about Iran and (mis)attribution of responsibility to Iranian sources than did participants who both engaged in hegemonic 9/11 commemoration practices and recalled this engagement before completing dependent measures.This evidence is consistent with the interpretation that observed effects of the manipulation are the result of engagement with hegemonic practices of 9/11 commemoration, not merely the result of reminders about the 9/11 attacks.Still, one may reasonably wonder whether responses about engagement with 9/11 commemoration practices are more a reflection of relevant individual differences, such as national or political identification, than an indicator of a person's actual engagement with commemoration practices.In that case, the association between self-reported 9/11 commemoration and responses to dependent measures may be a spurious result of their mutual correlation with this third, individual difference variable.In response to this alternative explanation, we note that results do not change when we control for political and national identification, some evidence that observed effects are independent of political and national identification.

General Discussion
Among other intellectual issues, a cultural psychology approach emphasizes the emergent character of 9/11 commemoration practices as an opportunity for the collaborative reproduction of cultural products-social representations of the collective past realized in material form (Hilton & Liu, 2017;Liu & Hilton, 2005;Moscovici, 1984)-that both reflect and direct current intergroup relations.In the reflect direction, the reconstructive memory hypothesis (H2) proposes that commemoration practices afford opportunities to reinterpret the meaning of the 9/11 attacks in light of current intergroup relations by misattributing greater responsibility for the attacks to Iranian sources.In the direct direction, the prospective affordance hypothesis (H1) proposes that engagement with evolving hegemonic practices of 9/11 commemoration extends belligerent vigilance to new cases of intergroup conflict (the JCPA) unrelated to the original 9/11 attacks.
Results provide evidence for both hypotheses.In Study 1, vigilance about the JCPA (H1) and misattribution of responsibility for the 9/11 attacks to Iranian sources (H2) was greater among participants who reported engagement with 9/11 commemoration than among participants who reported engagement with Labor Day observations.Results of Study 2 indicated that patterns of greater vigilance and misattribution as a function of engagement with 9/11 commemoration were more specifically true only of participants who reported actual engagement with hegemonic commemoration practices.Participants who reported engagement with hegemonic 9/11 practices and who recalled this engagement before completing dependent measures responded with greater vigilance about the JCPA and misattribution of Iranian responsibility for the 9/11 attacks than did participants who did not report engagement with hegemonic 9/11 practices or who did so after they had completed dependent measures.
Although these results are generally consistent with the hypotheses, they are not without ambiguity or limitations.
One point of ambiguity concerns the specificity of the reconstructive memory effect.In addition to hypothesized effects for (mis)attribution of responsibility to Iranian sources, we also observed similar effects for attribution of responsibility to actual sources (Studies 1 and 2) and (mis)attribution of responsibility to Saddam Hussein (only in Study 2), Because hegemonic forms of 9/11 commemoration are likely to emphasize actual sources of the attack, it is unsurprising that recall of engagement with such commemoration leads to greater attributions of responsibility to those sources.It is less clear why (reminders about) hegemonic forms of 9/11 in September 2015 would increase misattribution to the Iraqi regime of Saddam Hussein.One possibility that resonates with the current work is that hegemonic practices in 2015 continue to rehearse some of the same representations of events that led participants in earlier years to misattribute the 9/11 attacks to Saddam Hussein.An alternative possibility is that recall of engagement with 9/11 commemoration increases attribution of responsibility to any (plausible) source.
Although this alternative possibility does not account for results of Study 1, where the manipulation had no effects on attributions of responsibility to Saddam Hussein, the broader ambiguity remains a direction for future research.

Mere Reminder of 9/11 Attacks or Engagement With Commemoration Practice?
Another limitation of the research concerns ambiguity about the active ingredient of the experimental manipulation that is responsible for observed effects.Although we have proposed that observed effects derive from engagement with hegemonic forms of 9/11 commemoration, our procedure manipulated recall of such engagement rather than engagement per se.
vi Accordingly, one might reasonably wonder whether observed effects are not simply a replication of the well-known effect of reminders about the 9/11 attacks on belligerent reactions (with a possible extension of such research to consider belligerence toward unrelated sources and reconstruction of memory for the original 9/11 attacks).One response to this fair skepticism is to note that our prompt for the attribution of responsibility items included mention (and therefore reminder) of the 9/11 attacks for participants in both conditions.This casts doubt on the "mere reminder" explanation for observed results, at least for the responsibility attribution outcome.
Another response is to note the moderating effect of reported engagement with commemoration that we observed in Study 2. If mere reminders about the 9/11 attacks were sufficient to promote observed effects, then we would have observed these effects among all participants whom we prompted to recall engagement with 9/11 commemoration.Instead, we observed effects only among participants who had some engagement with commemoration available to recall, which again casts doubt on the "mere reminder" account.A conclusive investigation of this issue awaits further research.

Conclusion: Implications for Conceptions of Collective
Without denying the ambiguity of whether observed effects of commemoration (in our manipulation or in general) are due to the mere reminder about the original 9/11 attacks, we propose that a focus on precise internal mechanisms risks missing important implications of commemoration practice for the topic of collective memory.In particular, this focus can obscure the operation of collective motivation and agency via the intentionality of cultural practices.Reminders about the 9/11 attacks do not happen at random; instead, they more typically occur in the context of commemoration practices that creators have deliberately designed to afford remembering (Ghilani et al., 2017).Although many people make deliberate choices to engage in 9/11 commemoration practices, they also encounter them (and reminders about 9/11 attacks) in more inadvertent fashion without explicit intention to do so or despite explicit preferences otherwise.Regardless of how they came to encounter 9/11 commemoration practices or their more enduring personal inclinations regarding intergroup relations, engagement with hegemonic practices of 9/11 commemoration (which, at very least, constitute reminders of the original 9/11 attacks) is likely to promote action in accordance with the collective motivation inherent in the cultural artifact: in the current work, greater vigilance about the JCPA or misattribution of responsibility for the 9/11 attacks.What makes 9/11 commemoration a case of collective memory is not simply that it concerns collective versus personal identities, but instead that it involves cases of collective motivation and agency distributed across individuals distant in place and time through the mediation of cultural practices and other tools.
An optimistic implication of this perspective is that 9/11 commemoration need not inevitably promote belligerent responses.In theory, one could create practices of 9/11 commemoration with a different sort of intentionality that reflects and promotes less violent purposes.In other words, the effect of commemoration may depend on the content of associated cultural practices.Although we did not manipulate the content of commemoration in the research that we report here, it is the topic of our enduring work on a cultural psychology approach to collective memory.

Notes
i) Whereas this paragraph discusses the relationship between personal and collective identity as separate levels of self (i.e., following the manner of self-categorization theory; Turner et al., 1987), other research emphasizes how autobiographical memory and personal identity bear the influence of collective processes.Indeed, a cultural psychological analysis eschews a dichotomy between individual and social memory, instead placing the individual within the process of cultural discourse (Brockmeier, 2002).For example, research suggests that certain aspects of the "life setting" offer an anchor to fit one's personal life story into a broader collective story (Hammack, 2011).
ii) Throughout this article, we use the phrase "(reminders about) engagement" to emphasize the fact that, although our ultimate interest is engagement with hegemonic commemoration practice, what we manipulated in these studies was the opportunity for participants to recall or rehearse their engagement (or not) in 9/11 commemoration practices. i 14 th anniversary of the attacks in September 2015.In both studies, we manipulated the salience of 9/11 commemoration by instructing participants to report two weeks after the fact what (if anything) they did on September 11, 2015 to commemorate the 9/11 attacks.Participants then completed dependent measures concerning a potential case of intergroup conflict.We compared their responses to those of participants who recalled observance of a different event (Study 1) or who responded to dependent measures before reporting 9/11 commemoration (Study 2).

Suspicion
About Iran and the JCPAThe Gallup poll conducted surveys of public opinion during the JCPA negotiations throughout most of 2014 and 2015.We adapted four items from these polls to assess vigilance and suspicion regarding the deal, particularly the notion that the JCPA would facilitate the development and deployment of nuclear weapons.Participants used a scale from 1 (strongly disagree) to 7 (strongly agree) to indicate their agreement with the following items (α = .81):"The agreement makes it easier for the Iranian government to provide nuclear weapons to terrorists," "The agreement makes it easier for the Iranian government to attack the U.S. and Israel," "The U.S. should attack now, unilaterally if necessary, to destroy Iran's nuclear program," "Regardless of what its leaders say, the true purpose of Iran's nuclear program is to produce weapons."Responsibilityfor 9/11 AttacksParticipants used a scale from 0 (had no part/did not contribute) to 5 (a very large part/contributed very much) to indicate the extent to which each of five targets "contributed to the terrorist attacks on 9/11/2001."Two of the rating targets-Osama Bin Laden, the Saudi leader of al Qaeda who organized the attacks; and the Taliban, the rulers of Afghanistan who indirectly supported the attacks by harboring Bin Laden (r = .46,p < .001)-wereactual sources who bore more responsibility for the attacks than the other targets.Another two targets, President Mohammad Khatami and Ayatollah Khamenei (r = .89,p < .001),were prominent political figures in Iran during September 2001, who bore no responsibility for the attacks.We computed the mean of ratings for the Bin Laden and Taliban items and the Khatami and Khamenei items to serve as respective indicators of accurate and (false) Iran-relevant beliefs.To the extent that elites used the opportunity of the 2015 commemoration to link the 9/11 attacks to the JCPA agreement with Iran, one can hypothesize that participants will reconstruct memory of the attacks in ways that (incorrectly) attribute responsibility to the Iranian sources.A fifth and final target was Saddam Hussein, President of Iraq during September 2001, whom many Americans falsely believe was an accomplice in the 9/11 attacks.
Iran and the JCPA -What kinds of directive force does such 9/11 commemoration exert?Independent samples t-tests showed no effect of the manipulation on either national identification or political conservatism, ts < 1.65, ps > .10.Since national identification (r = .21)and political conservatism (r = .53)correlated with the outcome (vigilance), we controlled for these variables in an Analysis of Covariance (ANCOVA) to assess the effects of the manipulation on vigilance about Iran and the JCPA.Consistent with the prospective affordance hypothesis (H1), participants in the 9/11 condition expressed more suspicion about Iran and the JCPA (M adj = 3.79, 95% CI [3.51, 4.08]) than did participants in the Labor Day condition (M adj = 3.14, 95% CI [2.83, 3.44]), F(

Figures
Figures 1a and 1b.Vigilance about the Iran deal as a function of 9/11 commemoration salience, Studies 1 and 2. Horizontal bars represent unadjusted means.Shaded bands represent 95% confidence intervals. Figure2).

Figure 2 .
Figure 2. The interaction between salience of commemoration and level of commemoration engagement, Study 2. Horizontal bars represent unadjusted means.Shaded bands represent standard errors.
(BBC Staff, 2016)rpose of the JCPA was to block all of Iran's pathways to developing a nuclear weapon, with increased inspections by the International Atomic Agency to verify compliance(White House, 2016).In exchange, the JCPA dictated that the U.S., UN, and the European Union lift long-held sanctions related to Iran's nuclear program(BBC Staff, 2016).Parties started negotiations in February 2014, and they settled on terms in July 2015.The agreement was subject to nullification in the U.S. Congress, and public debate raged as the anniversary of the 9/11 attacks approached in September 2015.

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It was like any other day.I didn't do anything special.