One. Assassination by the US government has been illegal since 1976 Drone killings are acts of premeditated murder. Premeditated murder is a crime in all fifty states and under federal criminal law. These murders are also the textbook definition of assassination, which is murder by sudden or secret attack for political reasons.
In 1976 U.S. President Gerald Ford issued Executive Order 11905, Section 5(g), which states “No employee of the United States Government shall engage in, or conspire to engage in, political assassination.” President Reagan followed up to make the ban clearer in Executive Order 12333. Section 2.11 of that Order states “No person employed by or acting on behalf of the United States Government shall engage in, or conspire to engage in, assassination.” Section 2.12 further says “Indirect participation. No agency of the Intelligence Community shall participate in or request any person to undertake activities forbidden by this Order.” This ban on assassination still stands.
The reason for the ban on assassinations was that the CIA was involved in attempts to assassinate national leaders opposed by the US. Among others, US forces sought to kill Fidel Castro of Cuba, Patrice Lumumba of the Congo, Rafael Trujillo of the Dominican Republic, and Ngo Dinh Diem of South Vietnam.
That was one of the five reasons offered by author Bill Quigley. Quigley was only focusing on drone attacks. However if we look at the law as cited by the author we would also conclude that the war in Libya that resulted in the killing of Kaddaffi by what appears to be members of the "new regime" who could not have gotten to Khaddaffi without the direct intervention of NATO; can and may also fall under the same rubric. This is because if both direct and indirect assassination is illegal under US law (among other laws) and the war in Libya was, as far as I've researched, an indirect assassination of Khaddaffi, then the president of the United States did in fact break federal law (or at least whatever legal standing an executive order has).
For those confused about how I came to this conclusion they should revisit my earlier writings on the subject, (US admits to "Setting the Course" in Libya and The White House Libya Explanation Falls Short) There I explain in detail how all the rationalizations presented to the public do not stand up to law nor the claim that the US was somehow not "significantly involved".
Mind you. Had this been an act by Bush and co. we would be hearing it all day every day from certain quarters.