Rooted in decades of anti-Japanese and anti-Asian prejudice and triggered by the bombing of Pearl Harbor on Dec. 7, 1941, the wartime internment of 120,000 Nisei, American citizens of Japanese descent, and Issei, Japanese resident aliens, followed earlier restrictions on Japanese immigration, land ownership, and U.S. naturalization. After the attack, a mandatory curfew was imposed first on Japanese aliens and then on Japanese American citizens, and all were required to carry identification. On February 19, 1942, President Franklin Roosevelt issued Executive Order 9066, ordering the exclusion of all persons of Japanese descent, alien or citizen, from designated areas of Washington, Oregon, California, and Arizona for reasons of military necessity. People of Japanese American descent were ordered to report to assembly centers until camps could be built, were given only a few days to secure or dispose of their land, houses, and possessions, and were allowed to take 100 pounds per person or what they could carry. The confinement system included sixteen assembly centers, ten Justice Department camps, six citizen isolation centers, and ten internment camps in Utah, Arizona, Colorado, Wyoming, California, Idaho, and Arkansas that operated from 1942 to 1946. The Heart Mountain Relocation Center opened in 1942 and closed in November 1945, after which those held there were removed, given twenty-five dollars, and a rail pass to the destination of their choice. Former internees faced hostility, acute housing shortages, loss of jobs and businesses, and the need to begin life again, with recovery coming slowly after World War II. The Commission On Wartime Relocation and Interment of Civilians later concluded that the exclusion, expulsion, and incarceration of Japanese Americans during World War II were not justified by military necessity, but instead resulted from race prejudice, war hysteria, and a failure of political leadership.