http://en.wikipedia.org/wiki/Harry_S._Trumanhere's some of it:
The end of World War II was followed in the United States by uneasy and contentious conversion back to a peacetime economy. The president was faced with a sudden renewal of labor-management conflicts that had lain dormant during the war years, severe shortages in housing and consumer products, and widespread dissatisfaction with inflation, which at one point hit six percent in a single month.<62> In this polarized environment, there was a wave of destabilizing strikes in major industries, and Truman's response to them was generally seen as ineffective.<62> In the spring of 1946, a national railway strike, unprecedented in the nation's history, brought virtually all passenger and freight lines to a standstill for over a month. When the railway workers turned down a proposed settlement, Truman seized control of the railways and threatened to draft striking workers into the armed forces.<63> While delivering a speech before Congress requesting authority for this plan, Truman received word that the strike had been settled on his terms.<63> He announced this development to Congress on the spot and received a tumultuous ovation that was replayed for weeks on newsreels. Although the resolution of the crippling railway strike made for stirring political theater, it actually cost Truman politically: his proposed solution was seen by many as high-handed; and labor voters, already wary of Truman's handling of workers' issues, were deeply alienated.
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When he left office in 1953, Truman was one of the most unpopular chief executives in history. His job approval rating of 22 percent in the Gallup Poll as of February 1952 was actually lower than Richard Nixon's was in August 1974 at 24 percent, the month that Nixon resigned. Public feeling toward Truman grew steadily warmer with the passing years, however, and the period shortly after his death consolidated a partial rehabilitation among both historians and members of the general public. Since leaving office, Truman has fared well in polls ranking the presidents. He has never been listed lower than ninth, and most recently was seventh in a Wall Street Journal poll in 2005. He has also had his critics. After a review of information available to Truman on the presence of espionage activities in the U.S. government, Democratic Senator Daniel Patrick Moynihan concluded that Truman was "almost willfully obtuse" concerning the danger of American communism.