Clayton, John M(iddleton) (1796–1856)

US politician. He was a member of the Senate 1828–36, 1845–49, and again from 1852 until his death. As secretary of state, he negotiated, with the British diplomat Henry Lytton Bulwer (1801–1872), the Clayton-Bulwer Treaty 1850, providing for joint US-UK control of a planned canal across Central America. The treaty was abandoned 1901 when the Panama Canal was about to be built.