In 1965 (or 1963, according to one source), Buckley rejoined the CIA in what is now called the Special Activities Division. He may have been recruited by Ted Shackley, joining his Secret Team that had been involved with Edwin Wilson, Thomas Clines, Carl Jenkins, Rafael Quintero, Félix Rodriguez and Luis Posada Carriles, in the CIA assassination program. Leslie Cockburn pointed out in her book, "Out of Control" (1987), that Buckley was involved in approving CIA assassinations undertaken by the Shackley organizations. In his book, "Prelude to Terror" (2005) Joseph Trento claims that Buckley was "one of Shackley's oldest and dearest friends."