 In 1939–1940 he headed a committee to study the operation of administrative bureaus in the federal government.Brought back as assistant secretary of state on February 1, 1941, Acheson implemented much of United States economic policy aiding Great Britain and harming the Axis Powers.Acheson implemented the Lend-Lease policy that helped re-arm Great Britain and the American/British/Dutch oil embargo that cut off 95 percent of Japanese oil supplies and escalated the crisis with Japan in 1941.