Willkie vigorously supported the provision of aid to the Allies in Europe, which earned him the displeasure of the Republicans in Congress. He worked consistently for a more liberal Republican party and for Republication commitment to a post-war international organisation. Following America’s entry into World War Two, he travelled around the world, with President Roosevelt’s approval, visiting battlefields and war time leaders. On his return he wrote One World, describing his travels and meetings with Allies heads of state, ordinary citizens and soldiers, and making a plea for international understanding and cooperation. It sold more than a million copies. Willkie’s liberalism saw him losing ground in the Republican Party. In 1944 he lost the Republication presidential nomination to Thomas E Dewey. In August of that year he suffered a heart attack and died two months later. While he never held political office, he did exercise notable influence on American policy and ideology during this period.