Argument: Engagement in political assassinations is forbidden by US law
"U.S. policy on assassinations." CNN. November 4, 2002 -- "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."