One of the less prominent members of his party with no major legislation to his name, Austin nonetheless distinguished himself by belonging to the very small group of internationalist Republicans who opposed the neutrality legislation of the 1930s, advocated increases in military budgets, and believed that the United States should follow a more activist foreign policy.
After American intervention in World War II, Austin called for immediate planning for the postwar world. In 1942 the administration of President Franklin D. Roosevelt, keen to secure bipartisan support for its foreign policy initiatives, invited him to join the State Department's newly formed congressional foreign policy advisory group. In this capacity and as a key member of the Committee of Eight (leading senators who supported the creation of some form of postwar international organization), Austin was prominent in persuading the Republican Party to endorse this goal in its 1944 platform and likewise the establishment of international financial institutions and the United Nations (UN) Relief and Rehabilitation Administration. In 1942 Austin's internationalist stance cost him his position as informal Republican minority leader in the Senate, but in 1946 President Harry S. Truman appointed him the first U.S. ambassador to the UN.
Austin was sympathetic to the idea of an organization that would embody the highest universalist moral and legal principles. During the frequent Cold War crises of this period, more hard-line administration officials often bypassed him and his mission, and he was forced to defend positions that might have seemed to conflict with his personal predilections. An eloquent spokesman for the highest American and international ideals, he was nonetheless not a close advisor to any of the secretaries of state under whom he served and had little influence on policy formulation.
Austin's own perspective hardened as the Cold War developed and intensified, a process that the outbreak of the Korean War reinforced. He pushed through the UN resolution of 27 June 1950 that authorized military intervention by UN member states. In July, Austin pressed strongly for a unified command in Korea under U.S. leadership, a stance that irritated his colleagues in some of the allied and neutral delegations, as did his tendency to treat the war as a moral crusade in which the interests of the UN and the United States were indistinguishable. Following Chinese intervention in late 1950, Austin was instrumental in winning passage of the 1 February 1951 UN resolution condemning the crossing by communist Chinese troops of the 38th Parallel. Austin also firmly supported Truman's decisions to replace General Douglas MacArthur as commander in chief of the UN forces and to keep the war a limited conflict.
Troubled by poor health from late 1951 onward, in 1953 Austin retired to Burlington. By then a hard-line anticommunist, he became honorary chairman of the Committee of One Million, the objective of which was to exclude the People's Republic of China from the UN. Austin died on 25 December 1962 in Burlington.
Gaglione, Anthony. The United Nations under Trygve Lie, 1945–1953. Lanham, MD: Scarecrow, 2001.; Mazuzan, George T. Warren R. Austin at the U.N., 1946–1953. Kent, OH: Kent State University Press, 1977.