For Franklin D. Roosevelt, the spring of 1941 was a time of uncertainty and fear. Hitler's armies were poised to strike, but no one was sure where the next attack would come, and Churchill and members of Roosevelt's administration were urging him to intervene before it was too late. In this illuminating and comprehensive account of the American entry into World War II, Waldo Heinrichs shows that Roosevelt was not the vacillating, impulsive, and disorganized leader as he is often portrayed, but a cautious, rational man, capable of acting with great determination.A masterly account of a key moment in history, Threshold of War is both a distinguished work of scholarship and a moving narrative that captures the tension as Roosevelt, Churchill, Stalin, Stimson, Hull, and numerous others struggled to shape American policy in the climactic months before Pearl Harbour.