Japanese war crimes
The U.S. officially classified all 3,649 military and civilian casualties and destruction of military property at Pearl Harbor as non-combatants as there was no state of war between the U.S. and Japan when the attack occurred. Joseph B. Keenan, the chief prosecutor in the Tokyo Trials, says that the attack on Pearl Harbor not only happened without a declaration of war but was also a treacherous and deceitful act. In fact, Japan and the U.S. were still negotiating for a possible peace agreement which kept U.S. officials very distracted when Japanese planes bombed Pearl Harbor. Keenan explained the definition of a war of aggression and the criminality of the attack on Pearl Harbor:
Presidency of Franklin D. Roosevelt
The attack on Pearl Harbor raised concerns in the public regarding the possibility of sabotage by Japanese Americans. This suspicion was fed by long-standing racism against Japanese immigrants, as well as the findings of the Roberts Commission, which concluded that the attack on Pearl Harbor had been assisted by Japanese spies. The size of the Japanese population in Hawaii precluded mass internment in that territory, but there was strong popular support for the removal of Japanese from the West Coast. In February 1942, President Roosevelt signed Executive Order 9066, which provided for the relocation of hundreds of thousands of Japanese-American citizens and immigrants from the West Coast. They were forced to liquidate their properties and businesses and interned in hastily built camps in interior, harsh locations. Distracted by other issues, Roosevelt had delegated the decision for internment to Secretary of War Stimson, who in turn relied on the judgment of Assistant Secretary of War John J. McCloy. The Supreme Court upheld the constitutionality of the executive order in the 1944 case of "Korematsu v. United States". The internment order was rescinded shortly after the "Korematsu" decision, and Japanese-Americans were allowed to return to the West Coast. Many German and Italian citizens were also arrested or placed into internment camps.