Learn why, in the aftermath of the attack on Pearl Harbor by Japan, some Americans developed unfounded fears about their fellow Japanese American citizens and what they might do to sabotage America’s efforts in World War II. On February 19, 1942, President Franklin D. Roosevelt issued Executive Order 9066, an order that forced all Americans of Japanese descent into internment camps. All in all, 120,000 Japanese Americans—79,000 of whom were American citizens—were incarcerated, leaving behind their homes, their businesses, and their livelihoods. Many Japanese Americans were faced with conflicting allegiances and had to decide what it meant to be a loyal American.