Bobert: Assuming that you are referring to Saddam Hussein:

In 1976, President Gerald R. Ford issued Executive Order 11905 to clarify U.S. foreign-intelligence activities. In a section of the order labeled "Restrictions on Intelligence Activities," Ford concisely but explicitly outlawed political assassination:

                            5(g) Prohibition on Assassination. 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 Jimmy 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:

            2.11 No person employed by or acting on behalf of the United States Government shall engage in, or conspire to engage in, assassination.

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 Because no subsequent executive order or piece of legislation has repealed the prohibition, it remains in effect.