Taft was equally critical of President Franklin D. Roosevelt's foreign policies. When World War II began, Taft opposed American aid to the Allies, supporting the America First policies enunciated by ex-President Herbert Hoover and others and insisting that war would destroy American civil liberties and that Germany posed no danger to the Western Hemisphere. Following the U.S. entry into the war, Taft constantly assailed what he viewed as the excesses of domestic controls and propaganda while opposing the creation of a world bank or any other international organization apart from the United Nations (UN).
By 1946 Taft, nicknamed "Mr. Republican," had become a major figure within the cross-party conservative coalition that effectively dominated Congress. Immune to appeals for bipartisanship, as the Cold War developed he opposed high defense expenditures, voted in 1946 against the large American loan to Britain; complained that American military and economic support for Greece, Turkey, and the Marshall Plan were all too expensive; and opposed the creation of the North Atlantic Treaty Organization (NATO). He believed that America's atomic weapons safeguarded it from any foreign attack and that his country should not commit troops outside the Western Hemisphere.
When the Korean War began, Taft, de facto though not official leader of a Republican Senate majority, exploited the war to shore up both his party's and his own political fortunes in the impending 1952 presidential campaign, which the Republicans were determined not to lose as they had unexpectedly done to Truman in 1948. Taft reluctantly supported Truman's initial decision to commit forces to Korea, but after communist China's intervention in late 1950, Taft accused the president of mishandling the war. Taft also deplored the administration's failure to seek either a formal declaration of war or a congressional resolution authorizing the use of force in Korea. He laid much of the responsibility for the war on the administration's "bungling and inconsistent foreign policy." Taft even suggested that the United States might be well advised to withdraw from Korea and base its defenses upon a line running through the island positions of Taiwan and Japan. When Truman recalled General Douglas MacArthur in the spring of 1951, Taft defended the general, abandoning his customary restraint and publicly advocating MacArthur's preferred and highly provocative measures of bombing Chinese supply lines in Manchuria and including Guomindang (GMD, Nationalist) troops from the Republic of China (ROC) on Taiwan in UN forces.
Even though Taft found the extremist tactics of Senator Joseph R. MacCarthy personally distasteful, he tolerated them, believing that they would enhance the Republican Party's chances of victory. Campaigning for the 1952 Republican nomination, which he lost to the internationalist war hero Dwight D. Eisenhower, Taft harped constantly on the refrain that the Democratic administration had blundered unnecessarily into an expensive war that it could neither win nor end with honor, a theme that Eisenhower and other Republican candidates continually repeated. Named Republican majority leader after the election, a mellower Taft unsuccessfully attempted to rein in the excesses of McCarthyism. Taft died of cancer in New York City on 31 July 1953.
DeJohn, Samuel, Jr. "Robert A. Taft, Economic Conservatism, and Opposition to United States Foreign Policy, 1944–1951." Unpublished PhD diss., University of Southern California, 1976.; Matthews, Geoffrey. "Robert A. Taft, the Constitution and American Foreign Policy, 1939–53." Journal of Contemporary History 17(3) (July 1982): 507–522.; Patterson, James T. Mr. Republican: A Biography of Robert A. Taft. Boston: Houghton Mifflin, 1972.; Taft, Robert A. A Foreign Policy for Americans. Garden City, NY: Doubleday, 1951.; Wunderlin, Clarence E., Jr., ed. The Papers of Robert A. Taft. 2 vols. to date. Kent, OH: Kent State University Press, 1997–.