U.S. Attorney General In 1901, Knox was appointed as
US Attorney General by President
William McKinley and was re-appointed by President
Theodore Roosevelt. He served until 1904. While serving President Roosevelt, Knox worked hard to implement the concept of
Dollar Diplomacy. He told President Roosevelt: "I think, it would be better to keep your action free from any taint of legality," made in regard to the construction of the
Panama Canal. In domestic matters, Knox successfully prosecuted the
Northern Securities Company merger in
Northern Securities Co. v. United States, and the "Beef Trust" in
Swift & Co. v. United States.
U.S. Senator In June 1904, Knox was appointed by
Governor Samuel W. Pennypacker of
Pennsylvania to fill the unexpired term of the late
Matthew S. Quay in the
United States Senate. In 1905, he was
elected by the state legislature to fill the remainder of the full term for the US Senate seat (to 1909). Knox made an unsuccessful bid for the
Republican Party nomination in the
1908 U.S. presidential election.
U.S. Secretary of State In February 1909, President-elect
William Howard Taft nominated Senator Knox to be
Secretary of State. He was at first found to be constitutionally ineligible, because Congress had increased the salary for the post during his Senate term, thus violating the
Ineligibility Clause. The
Senate Judiciary Committee proposed the remedy of resetting the salary to its pre-service level, and the Senate passed it unanimously on February 11, 1909. Members of the
U.S. House of Representatives mounted more opposition to the relief measure and defeated it once. After a special procedural rule was applied, the measure was passed by a 173–115 vote. On March 4, 1909, the salary of the Secretary of State position was reverted from $12,000 to $8,000, and Knox took office on March 6. Knox felt that not only was the goal of diplomacy to improve financial opportunities, but also to use private capital to further U.S. interests overseas. When the Zionist Literary Society sought endorsement from the Taft administration, Knox recommended against approval, noting in his assessment that "problems of Zionism involve certain matters primarily related to the interests of countries other than our own." In spite of successes, "dollar diplomacy" failed to counteract economic instability and the tide of revolution in places like Mexico, the Dominican Republic, Nicaragua, and China.
Return to the Senate ,
Warren G. Harding,
Joseph Gurney Cannon, and Knox on March 4, 1921 Following his term of office, Knox resumed the practice of law in Pittsburgh. In 1916, Knox was elected by popular vote to the Senate from Pennsylvania for the first time, after passage of the
Seventeenth Amendment providing for such popular elections. He served from 1917 until his death in 1921. While a Senator, he was highly critical of the
Treaty of Versailles ending World War I, saying "this Treaty does not spell peace but war — war more woeful and devastating than the one we have but now closed". At the
1920 Republican National Convention, Knox was considered a potential compromise candidate who could unite the progressive and conservative factions of the party. Many thought that California Senator
Hiram Johnson would release his delegates to back his friend Knox, but Johnson never did.
Warren G. Harding instead emerged as the compromise candidate, and Harding went on to win the
1920 election. After the election, Knox urged President Harding to consider Andrew Mellon for the position of Secretary of the Treasury, and Mellon ultimately took the position. In April 1921, he introduced a Senate resolution to bring a formal end to American involvement in
World War I. It was combined with a similar House resolution to create the
Knox–Porter Resolution, signed by President
Warren G. Harding on July 2. ==Personal life==