The EO really only matters if we intend to do it ourselves. But we don't really have to be the ones to do the wet work. The EO can even provide plausible deniability when we give our assent to let somebody else do it. My money's on the Chinese, who will in turn use their influence on their regime agents to make it an inside job.
Covert taking out of thugs via an operation overseen by the Pentagon under order of congress {on need to know basis} and POTUS would save many of our service members lives. Ford and Carter's EO prohibiting assignations gave a green light to some of the worst dictators from 1976-present. Look at these time-lines and you'll see the connection. Ford's EO was written I think in 1975. Significant Terrorist Incidents, 1961-2003: A Brief Chronology
The heads of state supporting terrorist cells lost all fear of retribution from our government to make THEM personally pay for their actions. The prohibition was a huge mistake and sent the wrong message of do as you please we won't kill you for it.