How do historians define 'concentration camps' and which definitions apply to U.S. detention systems?
Executive summary
Historians treat "concentration camp" as a descriptive category with multiple, historically rooted definitions—key recurring elements are mass detention of civilians, detention outside normal judicial process, targeting of specific populations, and state control—while the most notorious examples (Nazi extermination camps) add systematic killing and industrial-scale murder to that base definition [1] [2] [3]. Whether U.S. detention systems qualify depends on which definition is used: under broad formulations (mass civilian detention without ordinary legal protections) many scholars and commentators argue modern U.S. immigration and wartime internment practices fit; under stricter, genocide-linked or extermination-focused definitions they do not [4] [5] [6].
1. What historians mean when they say “concentration camp”
A consensus among reference works and camp scholars is that a concentration camp is primarily a site for detaining civilians perceived as security risks or “undesirable” groups, usually by executive or military authority and often without usual judicial safeguards; this generic definition appears in major sources including the U.S. Holocaust Memorial Museum and Britannica [1] [3]. Historians also emphasize that the label covers a broad family of institutions differing in purpose and severity—some were punitive internment sites or instruments of forced labor (the Soviet Gulag), others were transitional or mass-extermination systems (Nazi Vernichtungslager)—so historical use requires specifying which features matter for a given comparison [2] [7].
2. Competing definitions: descriptive, moral, and legal thresholds
Scholars and public institutions deploy at least three thresholds when applying the term: a descriptive threshold—mass detention of civilians without usual legal process; a moral threshold—extreme inhumanity or systematic dehumanization; and a legal/functional threshold—policies of forced labor, deportation, or extermination [4] [6] [3]. Debates hinge on which threshold is decisive: some historians and human-rights scholars who stress the descriptive threshold argue that any state-run mass detention of noncombatant groups qualifies, whereas others insist on the additional element of systematic killing or industrialized murder to justify the rhetorical and moral weight of the term [5] [6].
3. Historical U.S. cases that fit historical definitions
The United States has precedents that historians routinely classify as concentration or internment camps under the descriptive definition: the mass internment of Japanese Americans during World War II is repeatedly cited as a canonical U.S. example, and earlier "reconcentración" and Native removal sites have also been characterized in similar terms by historians tracing the category’s global use [2] [8] [9]. Those episodes involved mass civilian detention by executive or military order, targeted by ethnicity, and often implemented without ordinary due process—meeting standard historical criteria for inclusion under the category [3].
4. Contemporary U.S. immigration detention: fitting some definitions, not others
When scholars and commentators compare modern ICE and CBP facilities to concentration camps, they typically invoke the descriptive definition—mass detention of civilians, detention conditions outside normal judicial process, and targeted populations (migrants/asylum seekers)—which several historians and analysts argue makes the term defensible as historical analogy [5] [10]. Critics—including institutions like the U.S. Holocaust Memorial Museum and some historians—warn against analogies that equate these facilities with Nazi extermination camps, noting the absence of state-directed, systematic killing of detainees in U.S. facilities and the different scale and function of Nazi camps [4] [1].
5. The politics of analogy and the limits of historical comparison
The choice to use the phrase “concentration camp” in public debate carries implicit moral and political agendas—activists may deploy a broad definition to dramatize humanitarian harms and press for policy change, while opponents may emphasize the most extreme historical referent to argue the comparison is inappropriate or offensive to Holocaust memory [5] [4]. Historians caution that rigorous comparison requires naming which definition is being used and being explicit about similarities and important differences; some commissions and researchers have found that intuitive judgments about what "looks like" a camp can override formal criteria, producing contested results [6] [8].
6. Bottom line: which definitions apply to U.S. systems?
By the standard historical definition focused on mass detention of civilians without normal legal protections, U.S. wartime internments (Japanese-American camps) and, under sustained scrutiny, many contemporary immigration detention practices meet the criterion and are widely discussed by scholars as part of the category [2] [5] [10]. By stricter definitions that require systematic killing, extermination, or industrialized murder—the defining feature of Nazi death camps—U.S. detention systems do not meet that threshold, a distinction emphasized by institutions and historians who reject Holocaust analogies that collapse these different kinds of atrocity [1] [4].