who is this person?
He was an American politician and diplomat
Howard Baker
Howard Henry Baker Jr. (November 15, 1925 June 26, 2014) was an American politician and diplomat who served as a United States Senator from Tennessee from 1967 to 1985. 
what's the 25th amendment to the constitution It  is ambiguous as to whether, in the enumerated circumstances, the vice president becomes the president, or merely assumes the "powers and duties" ,It also fails to define what constitutes "inability", or how questions concerning inability are to be resolved. what happened to it during 1987? Howard Baker became the White house chief of staff.
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Howard Baker [SEP] Introduction
Howard Henry Baker Jr. (November 15, 1925 June 26, 2014) was an American politician and diplomat who served as a United States Senator from Tennessee from 1967 to 1985. During his tenure, he rose to the rank of Senate Minority Leader and then Senate Majority Leader. A member of the Republican Party, Baker was the first Republican to be elected to the US Senate in Tennessee since the Reconstruction era. Known in Washington, D.C., as the "Great Conciliator", Baker was often regarded as one of the most successful senators in terms of brokering compromises, enacting legislation, and maintaining civility. For example, he had a lead role in the fashioning and passing of the Clean Air Act of 1970 with Democratic senator Edmund Muskie.