Roosevelt lost the Supreme Court battle, but a revolution in constitutional law took place. Thereafter the Government could legally regulate the economy. Roosevelt had pledged the United States to the "good neighbor" policy, transforming the Monroe Doctrine from a unilateral American manifesto into arrangements for mutual action against aggressors. He also sought through neutrality legislation to keep the United States out of the war in Europe, yet at the same time to strengthen nations threatened or attacked. When France fell and England came under siege in 1940, he began to send Great Britain all possible aid short of actual military involvement. When the Japanese attacked Pearl Harbor on December 7, 1941, Roosevelt directed organization of the Nation's manpower and resources for global war. Feeling that the future peace of the world would depend upon relations between the United States and Russia, he devoted much thought to the planning of a United Nations, in which, he hoped, international difficulties could be settled. As the war drew to a close, Roosevelt's health deteriorated, and on April 12, 1945, while at Warm Springs, Georgia, he died of a cerebral hemorrhage. .