In 1916, Baruch left Wall Street to advise President Woodrow Wilson on national defense and terms of peace. He served on the Advisory Commission to the Council of National Defense and, in 1918, became the chairman of the new War Industries Board. With his leadership, this body successfully managed the US's economic mobilization during World War I. In 1919, Wilson asked Baruch to serve as a staff member at the Paris Peace Conference. Baruch did not approve of the reparations France and Britain demanded of Germany, and supported Wilson's view that there needed to be new forms of cooperation, and supporting the creation of the League of Nations.[4]
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When the United States entered World War II, President Roosevelt appointed Baruch a special adviser to the director of the Office of War Mobilization. [...] In February 1943, Roosevelt invited Baruch to replace the widely criticized War Production Board head Donald M. Nelson.
http://en.wikipedia.org/wiki/Bernard_Baruch