Truman was a known private racist, coming from Mississippi, a state that enforced segregation. A president though, he tried to improve life for African Americans. This may have been due to the increasing importance of the black voters, but it was clear that he felt the current treatment of the African Americans was unacceptable.
During the cold war, the USSR propaganda had criticised American for its treatment of black Americans and that because of such treatment they shouldn't be able to criticise the USSR.
Truman knew, however, that it would be extremely difficult for civil rights legislation to be passed as Congress was made up of a lot of Southerners who were hostile to civil rights, and they were supported by a number of Northern Republicans. In 1948, some Southern Democrats went as far as setting up a new party, the Dixiecrats who were pro-segregationists. They won 2.4% of the national vote in the 1948 presidential election.
Tactics were used to block legislation being passed such as filibustering, where members of the congress would stand and talk for hours on end during the debate time for a bill therefore preventing it becoming law. However, Truman…