In 1976, President Ford issued Executive Order 11905 to clarify U.S. foreign intelligence activities. The order was enacted in response to the post-Watergate revelations that the CIA had staged multiple attempts on the life of Cuban President Fidel Castro.
In a section of the order labeled "Restrictions on Intelligence Activities," Ford outlawed political assassination: Section 5(g), entitled "Prohibition on Assassination," states: "No employee of the United States Government shall engage in, or conspire to engage in, political assassination."
Since 1976, every U.S. president has upheld Ford's prohibition on assassinations. In 1978 President Carter issued an executive order with the chief purpose of reshaping the intelligence structure. In Section 2-305 of that order, Carter reaffirmed the U.S. prohibition on assassination.
In 1981, President Reagan, through Executive Order 12333, reiterated the assassination prohibition. Reagan was the last president to address the topic of political assassination. Because no subsequent executive order or piece of legislation has repealed the prohibition, it remains in effect.
The ban, however, did not prevent the Reagan administration from dropping bombs on Libyan leader Moammar Gadhafi's home in 1986 in retaliation for the bombing of a Berlin discotheque frequented by U.S. troops.
Additionally, the Clinton administration fired cruise missiles at suspected guerrilla camps in Afghanistan in 1998 after the bombings of two U.S. embassies in Africa.
Following the September 11. 2001, attacks, the White House said the presidential directive banning assassinations would not prevent the United States from acting in self-defense.
According to an October 21, 2001, Washington Post article, President Bush in September of last year signed an intelligence "finding" instructing the CIA to engage in "lethal covert operations" to destroy Osama bin Laden and his al Qaeda organization.
White House and CIA lawyers believe that the intelligence "finding" is constitutional because the ban on political assassination does not apply to wartime. They also contend that the prohibition does not preclude the United States taking action against terrorists.