In April 1941, Lovett was named assistant secretary of war for air, a position that had been vacant since Roosevelt's 1933 inauguration. Lovett served with distinction, overseeing the massive expansion of the Army Air Forces and the procurement of huge numbers of aircraft during World War II. In awarding Lovett the Distinguished Service Medal in September 1945, President Harry Truman wrote, "He has truly been the eyes, ears and hands of the Secretary of War in respect to the growth of that enormous American airpower which has astonished the world and played such a large part in bringing the war to a speedy and successful conclusion."