Before becoming President, Taft, a Republican, was appointed to serve on the Superior Court of Cincinnati in 1887. In 1890, Taft was appointed Solicitor General of the United States and in 1891 a judge on the United States Court of Appeals for the Sixth Circuit. In 1900, President William McKinley appointed Taft Governor-General of the Philippines. In 1904, President Theodore Roosevelt appointed Taft Secretary of War in an effort to groom Taft, then his close political ally, into his handpicked presidential successor. Taft assumed a prominent role in problem solving, assuming on some occasions the role of acting Secretary of State, while declining repeated offers from Roosevelt to serve on the Supreme Court.
Riding a wave of popular support for fellow Republican Roosevelt, Taft won an easy victory in his 1908 bid for the presidency. In his only term, Taft's domestic agenda emphasized trust-busting, civil service reform, strengthening the Interstate Commerce Commission, improving the performance of the postal service, and passage of the Sixteenth Amendment. Abroad, Taft sought to further the economic development of nations in Latin America and Asia through "Dollar Diplomacy", and showed decisiveness and restraint in response to revolution in Mexico. The task-oriented Taft was oblivious to the political ramifications of his decisions, often alienated his own key constituencies, and was overwhelmingly defeated in his bid for a second term in the presidential election of 1912.
After leaving office, Taft spent his time in academia, arbitration, and the pursuit of world peace through his self-founded League to Enforce Peace. In 1921, after the First World War, President Warren G. Harding appointed Taft Chief Justice of the United States. He served in this capacity until shortly before his death in 1930.
Although he never got any recognition for his presidency and he himself hated being president, Taft has since been recognized as a good president by most historians for his efforts to bust up trusts and continue the policies of Theodore Roosevelt. In surveys of presidential scholars, Taft is usually ranked near the middle of lists of all American Presidents.