 At the war's end, Sir Frederick joined the Joint Intelligence Service and helped map out Australia's Cold War strategy that led to the formation of ASIO and ASIS.He is credited with helping crack a Russian spy ring attempting to operate in Australia.In 1948, he was appointed assistant secretary of the Defence of Department and two years later promoted to the position of chairman of the Repatriation Commission, the forerunner of the Department of Veterans' Affairs.