High Quality Content by WIKIPEDIA articles! Caspar Willard "Cap" Weinberger (August 18, 1917 – March 28, 2006), was an American politician, vice president and general counsel of Bechtel Corporation, and Secretary of Defense under President Ronald Reagan from January 21, 1981, until November 23, 1987, making him the third longest-serving defense secretary to date, after Robert McNamara and Donald Rumsfeld. He is also known for his role in the Strategic Defense Initiative and criminal indictments in the Iran-Contra Affair.