"Far less known than other leaders of World War II, Leahy was content to perform his services for his country and for the two presidents he served so closely, Franklin D. Roosevelt and Harry S. Truman. In his final job, the one he held longer than any other in his career, chief of staff to the commander in chief, he was the president's man. He spoke for the president, he represented the president, he advised the president, and he disagreed with the president when he believed he was wrong. But he did not make waves outside. He seldom gave interviews. When he made his occasional speeches, he talked on mundane subjects such as patriotism or what a proper naval education and naval career entailed. He kept silent- in public- on politics, on international affairs, on controversial issues. He made his opinions known where they mattered... Strictly a black-shoe sailor, Leahy did learn to value naval air and later the importance of air power. As he matured, he learned how the services complemented each other, and he was able to make balanced judgments which he recommended to the president. In the opinion of George Elsey, one-time assistant naval aide to President Truman, Leahy's greatest contribution was keeping the Joint Chiefs of Staff in line."