Today, the United States detains and incarcerates more non-citizen immigrants than any country in the world. Immigration and Customs Enforcement (ICE) detained more than 500,000 people across over 200 facilities in 2019. While the average length of time for which migrants are detained is relatively short – 70% of detainees are held for no more than one month – many are held for more than a year. The majority of these detainees have no past criminal history, and significant numbers had previously been granted the right to live in the U.S. permanently. The scale at which the U.S. has imprisoned immigrants may be exceptional, but migrant detentions have been rising in developed democracies around the world. Since the 1990s, detentions have also risen in the United Kingdom, France, Sweden and Australia.
We don’t typically think about this form of displacement at the hands of the state in the context of liberal democracies, yet the United States, in particular, has a history of targeted detainment that pre-dates large flows of immigrants across its borders. Following the attack on Pearl Harbor in 1941, the United States military forcibly removed over 110,000 Japanese Americans from their homes and incarcerated them in internment camps. The majority of those interned (62%) were American citizens at the time.
The case of Japanese Internment is instructive for several reasons. First, internment involved incarceration on a massive scale. The U.S. government forcibly relocated and imprisoned more than 86% of Japanese Americans living on the mainland in 1941. Second, like much of the contemporary policy conversation about combating “illegal” immigration, justifications for the mass dislocation of Japanese Americans were framed in starkly racial terms. John L. DeWitt, a driving force behind internment as head of the U.S. Army’s Western Defense Command, said that “racial affinities are not severed by migration. The Japanese race is an enemy race and while many second and third generation Japanese born on United States soil, possessed of United States citizenship have become ‘Americanized’ the racial strains are undiluted.”[1] Third, much like policies to combat unauthorized entry into the United States,[2] the internment of Japanese Americans was a popular measure at the time. A March 1942 poll by the American Institute of Public Opinion (later called Gallup) asked respondents “Do you think we are doing the right thing in moving Japanese aliens (those who are not citizens) away from the Pacific coast?” 93% of respondents said yes. Gallup’s follow-up survey in December 1942 revealed that just 35% of respondents thought that Japanese Americans should be allowed to return to their homes along the Pacific coast when the war ended.
Political scientists have thought about Japanese Internment a lot, but our focus tends to fall on its institutional implications: what did internment mean for the expansion of executive power? What can we learn from the Supreme Court’s initial decisions to uphold internment in Hirabayashi v. United States, Korematsu v. United States, and other key challenges to wartime restrictions on Japanese Americans? Often overlooked are internees themselves, for whom internment had profound, traumatic, and demobilizing political consequences. Maya Sen, Yamil Velez, and I examine these consequences using historical survey data from the period in a new working paper. I discuss our key findings and how they relate to current detention practices below.
How Do We Know?
Researchers conducted several large-scale surveys of Japanese Americans in the wake of internment. One of the most extensive is the Japanese-American Research Project (JARP), a nationally representative survey of 4,153 Japanese Americans living in the continental U.S. between 1962 and 1968.[3] Respondents to the JARP included three cohorts: 1,047 Issei, or immigrants from Japan who had settled in the United States before World War II; 2,304 Nisei, the U.S.-born children of Issei immigrants, and 802 Sansei, second generation Americans born to Nisei. Members of the same family are identified using family-specific codes, allowing researchers to study both the intergenerational impact of the internment experience and how different levels of exposure to internment (direct vs. hearing about internment through family accounts).
JARP asked respondents a series of questions about political attitudes and behavior. Respondents were asked about their level of interest in U.S. politics, whether non-family members had ever sought them out for political discussions (a proxy for the levels of political communication within communities), whether they believed that government elites were interested in the problems of everyday people, and whether they would have preferred to have leaders who opposed internment, accommodated it, or neither.[4]
These attitudinal measures of political engagement in the JARP provide meaningful insight into how victims of internment viewed the government. We can learn about the effects of internment on these attitudes by comparing people that were and weren’t interned (or learned about it from family members), looking at people interned for different lengths of time, and comparing outcomes for people interned in vastly different types of camps.
Our results broadly paint a picture of demobilization. Being interned is associated with about 13% of a scale point less interest in U.S. politics (responses are coded from 0, meaning no interest in politics at all, to 3, meaning a great deal of interest). People who were interned also tended to favor leaders who helped facilitate an orderly transition into internment (coded as a 1) to leaders who protested (coded as a -1) or did neither (coded as 0) by 11% of a scale point. Figure 1 summarizes the results from regressions of these outcomes on an indicator for internment, along with respondent age and gender.

The severity of the experience mattered. One way to think about the severity of internment is the length of time for which Japanese Americans were incarcerated. Conditional on being interned at all, the modal respondent to the JARP survey was interned for 3-4 years. The JARP data suggest that respondents who were incarcerated longer were significantly more likely to say that the government has no interest in the problems of the average man, less likely to report discussing politics with non-family members, and more likely to favor leadership that facilitated an orderly transition to internment rather than resisting it. Figure 2 summarizes the relationships between these measures of political engagement and respondents’ length of incarceration (in years).

The Internment Experience Across Camps
The places where people were interned gives us another way to think about the severity of the experience and its downstream consequences for political attitudes. The U.S. Army built ten major internment camps in which to imprison Japanese Americans living along the West Coast. Internment camp sites had to be: (1) far from strategic military targets along the coast (2) large enough to house thousands of people at the same time, and (3) already connected to transportation and utilities in order to allow for rapid settlement. Most internment camps were located on sites with pre-existing structures, such as stockyards and fairgrounds.[5]

Signs posted on telephone poles and post office windows notified Japanese Americans living in designated evacuation zones (see Figure 3) that they had approximately 6 days to travel to assembly centers (also former churches, race tracks, and stock yards) close to their homes. Internees waited at assembly centers until construction on internment camps was complete. They were transferred to internment camps as soon as camps were sufficiently complete and had capacity for them. Conditional on where internees were from, assignment to a specific camp was independent of their demographic or political characteristics. Assignment, in this sense, was quasi-random.
This feature of the internment process lets us identify the effects that living in specific camps had on the internees held there. This is worth investigating because internment experiences varied widely. Internees attacked a pro-cooperation leader of the Japanese American Citizens League (JACL) in the Manzanar camp, sparking a violent confrontation among internees and military police. This “Manzanar uprising” left two dead, nine others injured, and a score of internees jailed for participation in the violence. The struggle to access basic resources was also a recurrent theme in some camps. Agricultural workers went on strike at the Tule Lake internment camp after authorities refused to pay compensation to a widow whose husband died in a trucking accident. The military responded by bringing in internees from the Poston and Topaz camps as strike-breakers. To internees, experiences like this sent a powerful signal that the government would not provide for their safety or fundamental needs. Accordingly, people interned in camps that witnessed strikes or episodes of violence may have suffered even more demobilizing consequences than people who did not.
The JARP data largely bears this out. People interned in camps where strikes or violence broke out among internees were less likely to show interest in politics, less likely to engage in political communication with non-family members, less likely to favor leaders who resisted internment, and more likely to say that the government had no interest in addressing the problems of everyday people.
Why Demobilization?
These results also shed some light on why the consequences of internment were demobilizing for Japanese Americans, rather than the opposite. While we know that racially targeted policies can mobilize affected groups in some cases, the key difference in this case was that the internment experience fractured the Japanese-American community. Violent uprisings at Tule lake and Manzanar were extreme examples of constant tension between segments of the Japanese-American community that wanted to cooperate with internment and segments that wanted to resist. If there was no consensus about how to react to the internment experience, what did Japanese Americans have to mobilize around? Internment also disrupted family life and eroded communication between generations. Barracks life meant that internees were spending meals and workdays with members of their work detail, rather than family members. Sansei accounts of internment often mention sensing the extraordinary toll that incarceration took on their parents and grandparents – one study reported that twice as many fathers who were interned died before the age of 60 relative to fathers who were not[6]– but recount that older relatives were reluctant to discuss their internment experience.

Citizenship, Family, and the Future
There are two other things worth pointing out about these results. First, they are consistent with first-person, qualitative accounts of internment. “I could not believe that my country would do this to me,” one Nisei interviewee told researchers at the Nisei Project,[7] “especially when I had been a proud and loyal American.” Another reported that the internment experience “really emphasized that I didn’t belong in this country.” These echo contemporary accounts of dehumanization and marginalization voiced by people detained at the border or otherwise held in ICE custody, and they suggest that mass incarceration experiences lead to a disinvestments in civic participation that persist years after incarceration itself ends. Second, these results also suggest that people who only experienced internment via family members (Family-Only Exposure in the plots) still suffered political demobilization. This is particularly relevant to modern detention policy because many detainees have family members who are citizens living in the United States. The indirect effects that detainment has on family members is an area that requires a great deal of future research, but one thing we can learn from our history of internment is that it leads to political detachment even among those who don’t experience it personally.
[1] Commission on Wartime Relocation and Internment of Civilians. (1997). Personal justice denied: Report of the Commission on Wartime Relocation and Internment of Civilians. Washington DC: The Civil Liberties Public Education Fund and Seattle, WA: University of Washington Press.
[2] While public opinion in the United States has trended in favor of more legal immigration over the past few years, large proportions of Americans still view increasing border security along the U.S.-Mexico border and the deportation of undocumented immigrants as important policy priorities.
[3] Levine, Gene. N. 1997. “Japanese-American Research Project (JARP): A Three-Generation Study, 1890-1966.” ICPSR08450-v2
[4] Survey participants were also asked whether or not they voted and which major political party they supported, if any. While turnout and vote choice are usually important measures of engagement, several features of the target population make them less relevant to the discussion of Japanese Americans. First, more than 40% of the older Issei cohort were non-citizens at the time JARP was conducted, making them ineligible to vote. Additionally, 40% of the youngest Sansei cohort were under 21 – then the legal voting age – at the time JARP was conducted, making them ineligible to vote. The Nisei cohort was never asked about turnout directly. The impact that internment might have had on vote choice is also far from clear. While Japanese Internment was authorized by a Democratic president, prominent Republican politicians in California[4], Oregon and Washington supported internment.
[5] Ng, Wendy. 2002. Japanese American Internment During World War II: A History and Reference Guide. Greenwood Press.
[6] Nagata, Donna K., Jackie H. J. Kim, and Teresa U. Nguyen. “Processing Cultural Trauma: Intergenerational Effects of the Japanese American Incarceration.” Journal of Social Issues. 2015. 71(2).
[7] A survey of 520 Nisei who had been interned s funded by the University of Michigan Center for Japanese Studies, the University of Michigan Office of the Vice Provost for Academic and Multicultural Affairs, and the Civil Liberties Public Education Fund. Reprinted in Nagata, Donna K., Jackie H. J. Kim, and Teresa U. Nguyen. “Processing Cultural Trauma: Intergenerational Effects of the Japanese American Incarceration.” Journal of Social Issues. 2015. 71(2).