Of 127,000 Japanese Americans living in the continental United States at the time of the Pearl Harbor attack, 112,000 resided on the West Coast. About 80,000 were Nisei (literal translation: "second generation"; American-born Japanese with U.S. citizenship) and Sansei ("third generation"; the children of Nisei). The rest were Issei ("first generation") immigrants born in Japan who were ineligible for U.S. citizenship under U.S. law.
Japanese Americans were incarcerated based on local population concentrations and regional politics. More than 110,000 Japanese Americans in the mainland U.S., who mostly lived on the West Coast, were forced into interior camps. However, in Hawaii, where 150,000-plus Japanese Americans composed over one-third of the population, only 1,200 to 1,800 were also interned. The internment is considered to have resulted more from racism than from any security risk posed by Japanese Americans. Those who were as little as 1/16 Japanese, orphaned infants, and anyone with—in the words of the architect behind the internment program, Colonel Karl Bendetsen—"one drop of Japanese blood" were placed in the internment camps.
Roosevelt authorized the deportation and incarceration with Executive Order 9066, issued on February 19, 1942, which allowed regional military commanders to designate "military areas" from which "any or all persons may be excluded." This authority was used to declare that all people of Japanese ancestry were excluded from the West Coast, including all of California and parts of Oregon, Washington, and Arizona, except for those in government camps. Approximately 5,000 Japanese Americans relocated outside the exclusion zone before March 1942, while some 5,500 community leaders had been arrested immediately after the Pearl Harbor attack and thus were already in custody. The majority of nearly 130,000 Japanese Americans living in the U.S. mainland were forcibly relocated from their West Coast homes during the spring of 1942.
The United States Census Bureau assisted the internment efforts by spying and providing confidential neighborhood information on Japanese Americans. The Bureau denied its role for decades, but it became public in 2007. In 1944, the U.S. Supreme Court upheld the constitutionality of the removal by ruling against Fred Korematsu's appeal for violating an exclusion order. The Court limited its decision to the validity of the exclusion orders, avoiding the issue of the incarceration of U.S. citizens without due process.
In 1980, under mounting pressure from the Japanese American Citizens League and redress organizations, President Jimmy Carter opened an investigation to determine whether the decision to put Japanese Americans into concentration camps had been justified by the government. He appointed the Commission on Wartime Relocation and Internment of Civilians (CWRIC) to investigate the camps. The Commission's report, titled Personal Justice Denied, found little evidence of Japanese disloyalty at the time and concluded that the incarceration had been the product of racism. It recommended that the government pay reparations to the internees. In 1988, President Ronald Reagan signed into law the Civil Liberties Act of 1988 which apologized for the internment on behalf of the U.S. government and authorized a payment of $20,000 (equivalent to $42,000 in 2018) to each camp survivor. The legislation admitted that government actions were based on "race prejudice, war hysteria, and a failure of political leadership." The U.S. government eventually disbursed more than $1.6 billion (equivalent to $3,390,000,000 in 2018) in reparations to 82,219 Japanese Americans who had been interned and their heirs.
Due in large part to socio-political changes stemming from the Meiji Restoration—and a recession caused by the abrupt opening of Japan's economy to the world market—people began emigrating from the Empire of Japan in 1868 to find work to survive. From 1869 to 1924 approximately 200,000 immigrated to the islands of Hawaii, mostly laborers expecting to work on the islands' sugar plantations. Some 180,000 went to the U.S. mainland, with the majority settling on the West Coast and establishing farms or small businesses. Most arrived before 1908, when the Gentlemen's Agreement between Japan and the United States banned the immigration of unskilled laborers. A loophole allowed the wives of men already in the US to join their husbands. The practice of women marrying by proxy and immigrating to the U.S. resulted in a large increase in the number of "picture brides."
As the Japanese-American population continued to grow, European Americans on the West Coast resisted the new group, fearing competition and exaggerating the idea of hordes of Asians keen to take over white-owned farmland and businesses. Groups such as the Asiatic Exclusion League, the California Joint Immigration Committee, and the Native Sons of the Golden West organized in response to this "Yellow Peril." They lobbied successfully to restrict the property and citizenship rights of Japanese immigrants, as similar groups had previously organized against Chinese immigrants. Several laws and treaties attempting to slow immigration from Japan were introduced beginning in the late 19th century. The Immigration Act of 1924, following the example of the 1882 Chinese Exclusion Act, effectively banned all immigration from Japan and other "undesirable" Asian countries.
The 1924 ban on immigration produced unusually well-defined generational groups within the Japanese-American community. The Issei were exclusively those who had immigrated before 1924; some desired to return to their homeland. Because no new immigration was permitted, all Japanese Americans born after 1924 were, by definition, born in the U.S. and automatically U.S. citizens. This Nisei generation were a distinct cohort from their parents. In addition to the usual generational differences, Issei men had been typically ten to fifteen years older than their wives, making them significantly older than the younger children of their often large families. U.S. law prohibited Japanese immigrants from becoming naturalized citizens, making them dependent on their children to rent or purchase property. Communication between English-speaking children and parents who spoke mostly or completely in Japanese was often difficult. A significant number of older Nisei, many of whom were born prior to the immigration ban, had married and already started families of their own by the time the US joined World War II.
Despite racist legislation that prevented Issei from becoming naturalized citizens (and therefore from owning property, voting, or running for political office), these Japanese immigrants established communities in their new hometowns. Japanese Americans contributed to the agriculture of California and other Western states, by introducing irrigation methods that enabled the cultivation of fruits, vegetables, and flowers on previously inhospitable land.
In the 1930s the Office of Naval Intelligence (ONI), concerned by Imperial Japan's rising military power in Asia, began conducting surveillance on Japanese-American communities in Hawaii. From 1936, at the behest of President Roosevelt, the ONI began compiling a "special list of those who would be the first to be placed in a concentration camp in the event of trouble" between Japan and the United States. In 1939, again by order of the President, the ONI, Military Intelligence Division, and FBI began working together to compile a larger Custodial Detention Index. Early in 1941, Roosevelt commissioned Curtis Munson to conduct an investigation on Japanese Americans living on the West Coast and in Hawaii. After working with FBI and ONI officials and interviewing Japanese Americans and those familiar with them, Munson determined that the "Japanese problem" was nonexistent. His final report to the President, submitted November 7, 1941, "certified a remarkable, even extraordinary degree of loyalty among this generally suspect ethnic group." A subsequent report by
Kenneth Ringle, delivered to the President in January 1942, also found little evidence to support claims of Japanese-American disloyalty and argued against mass incarceration.
After Pearl Harbor
San Francisco Examiner, February 1942
A Japanese American unfurled this banner in Oakland, California the day after the Pearl Harbor attack. This Dorothea Lange photograph was taken in March 1942, just prior to the man's internment.
Children at the Weill public school in San Francisco pledge allegiance to the American flag in April 1942, prior to the internment of Japanese Americans.
American public opinion initially stood by the large population of Japanese Americans living on the West Coast, with the Los Angeles Times characterizing them as "good Americans, born and educated as such." Many Americans believed that their loyalty to the United States was unquestionable.
But, six weeks after the attack, public opinion along the Pacific began to turn against Japanese Americans living on the West Coast, as the press and other Americans became nervous about the potential for fifth column activity. Though the administration (including President Franklin D. Roosevelt and FBI Director J. Edgar Hoover) dismissed all rumors of Japanese-American espionage on behalf of the Japanese war effort, pressure mounted upon the administration as the tide of public opinion turned against Japanese Americans. Civilian, law enforcement, and military authorities had serious concerns about the loyalty of the ethnic Japanese after the Niihau incident which immediately followed the attack on Pearl Harbor, when a civilian Japanese national and two Hawaiian-born ethnic Japanese on the island of Ni'ihau violently freed a downed and captured Japanese naval airman, attacking their fellow Ni'ihau islanders in the process.
Several concerns over the loyalty of ethnic Japanese seemed to stem from racial prejudice rather than any evidence of malfeasance. The Roberts Commission report, which investigated the Pearl Harbor attack, was released on January 25 and accused persons of Japanese ancestry of espionage leading up to the attack. Although the report's key finding was that General Walter Short and Admiral Husband E. Kimmel had been derelict in their duties during the attack on Pearl Harbor, one passage made vague reference to "Japanese consular agents and other... persons having no open relations with the Japanese foreign service" transmitting information to Japan. It was unlikely that these "spies" were Japanese American, as Japanese intelligence agents were distrustful of their American counterparts and preferred to recruit "white persons and Negroes." However, despite the fact that the report made no mention of Americans of Japanese ancestry, national and West Coast media nevertheless used the report to vilify Japanese Americans and inflame public opinion against them.
The fact that nothing has happened so far is more or less . . . ominous, in that I feel that in view of the fact that we have had no sporadic attempts at sabotage that there is a control being exercised and when we have it it will be on a mass basis.
He further stated in a conversation with California's governor, Culbert L. Olson,
There's a tremendous volume of public opinion now developing against the Japanese of all classes, that is aliens and non-aliens, to get them off the land, and in Southern California around Los Angeles—in that area too—they want and they are bringing pressure on the government to move all the Japanese out. As a matter of fact, it's not being instigated or developed by people who are not thinking but by the best people of California. Since the publication of the Roberts Report they feel that they are living in the midst of a lot of enemies. They don't trust the Japanese, none of them.
DeWitt, who administered the internment program, repeatedly told newspapers that "A Jap's a Jap" and testified to Congress,
I don't want any of them [persons of Japanese ancestry] here. They are a dangerous element. There is no way to determine their loyalty... It makes no difference whether he is an American citizen, he is still a Japanese. American citizenship does not necessarily determine loyalty... But we must worry about the Japanese all the time until he is wiped off the map.
DeWitt also sought approval to conduct search and seizure operations aimed at preventing alien Japanese from making radio transmissions to Japanese ships. The Justice Department declined, stating that there was no probable cause to support DeWitt's assertion, as the FBI concluded that there was no security threat. On January 2, the Joint Immigration Committee of the California Legislature sent a manifesto to California newspapers which attacked "the ethnic Japanese," who it alleged were "totally unassimilable." This manifesto further argued that all people of Japanese heritage were loyal subjects of the Emperor of Japan; the manifesto contended that Japanese language schools were bastions of racism which advanced doctrines of Japanese racial superiority.
Those who were as little as 1/16 Japanese could be placed in internment camps. There is evidence supporting the argument that the measures were racially motivated, rather than a military necessity. Bendetsen, promoted to colonel, said in 1942, "I am determined that if they have one drop of Japanese blood in them, they must go to camp."
Presidential Proclamation 2537 was issued on January 14, 1942, requiring aliens to report any change of address, employment, or name to the FBI. Enemy aliens were not allowed to enter restricted areas. Violators of these regulations were subject to "arrest, detention and internment for the duration of the war."
On February 13, the Pacific coast Congressional subcommittee on aliens and sabotage recommended to the President immediate evacuation of "all persons of Japanese lineage and all others, aliens and citizens alike" who were thought to be dangerous from "strategic areas," further specifying that these included the entire "strategic area" of California, Oregon, Washington, and Alaska. On February 16 the President tasked Secretary of WarHenry L. Stimson with replying. A conference on February 17 of Secretary Stimson with assistant secretary John J. McCloy, Provost Marshal General Allen W. Gullion, Deputy chief of Army Ground ForcesMark W. Clark, and Colonel Bendetsen decided that General DeWitt should be directed to commence evacuations "to the extent he deemed necessary" to protect vital installations.