Thomas J. Devine
Thomas J. Devine (born December 9, 1926) in Rochester, New York, a 1949 B.S. M.I.T. graduate , worked for the CIA, and was an oil-wildcatting associate of George H. W. Bush. Devine helped Bush found Zapata Offshore in 1953 and he was an unnofficial foreign affairs advisor to Representative Bush in the 1960s. He accompanied Bush on a trip to Vietnam from 26 December 1967-11 January 1968, for which he was issued an interim top-secret clearance by the US Department of Defense. 
Devine married Alexandra Mills of Hobe Sound, FL, in April, 1973. William B. Macomber, Jr., best man in the 1946 wedding of Nancy Walker Bush Ellis, was Devine's best man. Macomber's brother, Celanese Corporation president, John D. Macomber, appointed Devine as a vice president (1973).  John D. Macomber is the longtime mentor and business associate of Michael L. Ainslie , second husband  of Suzanne B. Hooker, daughter of Edward Gordon Hooker , the deceased school roommate of George HW Bush and step-nephew and oil exploration business partner  George de Mohrenschildt, a petroleum geologist and professor who befriended Lee Harvey Oswald in the summer of 1962 and maintained that friendship until Oswald's death two days after the assassination of U.S. President John F. Kennedy.
Devine's friendship and "close relationship" with Bush Sr. continued as Bush was first made US Ambassador to the United Nations (from 1971-1973), then nominated as Director of the CIA (November 1975).