War Comes to America: The Road to Pearl Harbor, August to December 1941
We have sought no shooting war with Hitler. We do not seek it now. . . . But when you see a rattlesnake poised to strike, you do not wait until he has struck before you crush him.
Franklin D. Roosevelt, September 11, 19411
On September 4, 1941 a British aircraft on patrol over the North Atlantic spotted a German U-boat. The crew alerted a nearby American destroyer, USS Greer, dropped four depth charges and left the Greer to give chase alone. The U-boat, turned on its new pursuer and, not knowing the vessel's nationality, fired a torpedo. Undamaged, the destroyer replied with eight depth charges. The U-boat fired a second salvo, and then ran. Three-and-a-half hours and eleven depth charges later the Greer broke off the chase. It was an ambiguous incident, but it gave FDR an excuse to escalate his naval commitment to the Allies. On September 11, he broke the news to America; a German submarine had fired "first" and "without warning" on an American destroyer. This act of "piracy" was evidence of the "Nazi design to abolish the freedom of the seas." Henceforth the U.S. Navy would seek out all German and Italian raiders in what Roosevelt vaguely described as "waters, the protection of which is necessary for American defense," and "shoot on sight." This, in all but name, was a declaration of naval war. 2
Polls suggested that 62 percent of Americans supported Roosevelt's action. Few changed their minds when the facts of the Greer incident became clear. Roosevelt immediately put this support to work. From September 16 onward, British convoys traveled with U.S. naval escorts. 3 The public also pressed for action in East Asia, but here Roosevelt was less eager to provoke conflict. Japanese-American relations ground toward war regardless.
By September 1941, Japan and the United States were set on a collision course. Japan had embarked on a spiral of conquest in China, but