Arsenal of Democracy

"Arsenal of Democracy" was the central phrase used by U.S. President Franklin D. Roosevelt in a radio broadcast on the threat to national security, delivered on December 29, 1940—nearly a year before the United States entered the Second World War (1939–1945). Roosevelt promised to help the United Kingdom fight Nazi Germany by selling them military supplies while the United States stayed out of the actual fighting. The president announced that intent a year before the Attack on Pearl Harbor (7 December 1941), at a time when Germany had occupied much of Europe and threatened Britain.

Nazi Germany was allied with Fascist Italy and the Empire of Japan (the Axis powers). At the time, Germany and the Soviet Union had signed a non-aggression treaty under the Molotov–Ribbentrop Pact, and had jointly effected the Invasion of Poland (1939), a Realpolitik deal that remained effective until Operation Barbarossa, the Nazi invasion of the Soviet Union, in 1941.

Roosevelt's address was a call to arms for supporting the Allies in Europe, and, to a lesser extent, the Republic of China, in total war against Nazi Germany and Imperial Japan. "The great arsenal of democracy" came to specifically refer to the industry of the U.S., as the primary supplier of material for the Allied war effort.

"Arsenal of democracy" refers to the collective efforts of American industry in supporting the Allies, which efforts tended to be concentrated in the established industrial centers of the U.S., such as Detroit, Cleveland, Philadelphia, Buffalo, Rochester, Chicago, New York, and Pittsburgh, among other cities.^[1]