While those critiques frequently included complex legal challenges, one of them was fairly straightforward. Jaffer would often make the case that even if many people considered President Barack Obama a good and honest man, his bureaucracy for secret killing should not be built on trust alone. Rather, it required publicly demonstrable legality and efficacy — the idea being that those powers would one day be handed off to a new president.

Last week, the scenario at the heart of Jaffer's argument ceased to be rhetorical.

President-elect Donald Trump has been notoriously vague when describing his counterterrorism vision — arguing that he doesn't want to telegraph his secret plans — but if his vows to "bomb the shit out of" the Islamic State and kill the family members of suspected terrorists are any indication, the next four years are likely to include continued, or increased, lethal American operations abroad. If that's the case, Trump will have at his disposal a host of executive power precedents set by the Obama administration.