FDR spent the last four years of his life—from 1941 until his death in 1945—as a wartime president. Those four years are the stuff of legend (read more about it in Shmoop History). By the war's end, the United States had left the Great Depression behind and become one of the most powerful nations in the world.
During the war, Roosevelt deployed all of the talents he had used domestically to lead the war effort. He used the fireside chats to explain the war to the American people and enlist their support in helping win it. He also used the close relationships he had built with the press to give him wiggle room in which to make difficult decisions. And he used the relationships he had built with the country's European allies (especially his friendship with Winston Churchill) to both plan the war and the world order that followed.
FDR's record during the war was not flawless. Today, his decision to imprison thousands of Japanese-Americans is probably viewed as his most controversial action. In 1942, responding to fears of a Japanese invasion of the American mainland in the wake of the Pearl Harbor attack, Roosevelt signed Executive Order 9066. 110,000 Japanese-Americans were given a week to dispose of their property, rounded up and sent to camps in the desert.41 There, they were watched by searchlights and surrounded by watchtowers and barbed wire. The majority of them—70%—were American citizens.42
Roosevelt has also been criticized by some for failing to stop the Holocaust. As early as 1942, Jewish leaders briefed FDR on the atrocities unfolding in Nazi-occupied Europe. Although Roosevelt publicly spoke out against the genocide, he refused to divert military resources from efforts to win the war. When Jewish leaders proposed that he bomb the concentration camp at Auschwitz and the rail lines leading to it, Roosevelt refused, believing that the best way to help the Jews would be to win the war as quickly as possible.43
Neither of these decisions significantly damaged Roosevelt's public image. Back home, the economy was improving; even before Japan and Germany surrendered in 1945, the war had helped to alleviate the nation's economic problems. By 1943, the army of jobless workers had disappeared.44 Millions of Americans were employed as soldiers, nurses, sailors, pilots and mechanics on the war front, and wartime production in factories employed millions more. The war established Roosevelt's persona as a national leader, and many Americans who had opposed the social and economic policies of the New Deal rallied behind his leadership of the war effort.