With the approach of the presidential election of 1908, President Roosevelt reiterated his pledge not to accept another nomination, and threw his immense influence in favour of Mr Taft.
The government of Great Britain let it be known that its patience was not inexhaustible, while the senate of the United States declared that it would support President Roosevelt in his efforts for the amelioration of the condition of the inhabitants of the Congo.
The spontaneous yet successful effort made by President Roosevelt in 1905 to bring together the Russian and Japanese governments, and to secure their appointing delegates to discuss terms of peace, although not strictly mediation, was closely akin to it.
Mr Taft gained great influence among the more conservative Filipinos, and their entreaties to him to remain influenced him to decline the offer of a place upon the Supreme bench offered by President Roosevelt in 1902.
In 1900 he was appointed ambassador to Italy by President McKinley, and five years later was transferred by President Roosevelt to Russia.
Reports of territorial encroachments aroused much sympathy with Liberia in America and led in February 1909 to the appointment by President Roosevelt of a commission which visited Liberia in the summer of that year to investigate the condition of the country.
Astute and unscrupulous manipulation of the stock markets, and a capacity for the hardest of bargaining and the most determined warfare against his rivals, had their place in this success, and Harriman's methods excited the bitterest criticism, culminating in a stern denunciation from President Roosevelt himself in 1907.
By a law of April 1906 the U.S. consular service was reorganized and graded, the office of consul-general being divided into seven classes, and that of consul into nine classes; and on June 27 an executive order was issued by President Roosevelt governing appointments and promotions.
In 1907 he was appointed by President Roosevelt a member of the Isthmian Canal Commission, with the rank of lieutenant-colonel, and soon afterwards was made its chairman and chief engineer.
In 1905 he was appointed by President Roosevelt a member of the Interstate Commerce Commission and was retained by President Taft, serving for eight years, part of the time as chairman.