But with these benefits come real risks, including, most notably, as Obama stated, that “the very precision of drone strikes and the necessary secrecy often involved in such actions can end up shielding our government from the public scrutiny that a troop deployment invites.”

To guard against drones’ becoming what Obama feared could be an overused “cure-all for terrorism,” the former president heavily regulated their use outside of active war zones and eventually shared the applicable policy frameworks and limited-strike data with the public. Executive-branch officials like us took pride in fastidious adherence to these administrative rules. The process both provided a healthy level of rigor to strike decisions and constrained the availability of drone strikes in certain borderline cases, like when intelligence pinpointing the location of a high-value terrorist target was strong but not overwhelming. High-level bureaucrats from across numerous agencies spent endless hours in the White House Situation Room, and in bunkerlike offices suitable for classified information back at their home agencies, designing the drone policy from the ground up, considering proposed drone strikes and whether they met the standards Obama set, even on occasion proposing tweaks to those rules when they thought they were necessary to meet operational exigencies. Where public scrutiny was not initially encouraged, significant bureaucratic scrutiny was installed through a labyrinth of top-secret policies and rules.

But in so doing, senior officials almost certainly sacrificed the solution Obama had suggested was possible to manage drones’ siren song: a comprehensive counterterrorism strategy. The tactics of drone operations were all-absorbing—the definitions, the target approvals, the moralistic but private debate. Managing their use left little space for broader questions in the Situation Room about whether objectives were actually being met, or about the price of failure, or about whether nonmilitary efforts would be more appropriate.

The narrow objective for drone strikes, of course, is to kill the terrorists who are targeted and thus remove them from the battlefield. By that standard, the program may be deemed a success insofar as, according to government-released statistics, the program has resulted in the deaths of more than 3,000 combatants. It is worthwhile to note, however, that there is significant gap between how the government and NGOs investigate and calculate combatant and civilian casualties in the aftermath of strikes, which results in estimates from NGOs of far higher numbers of civilian casualties (and correspondingly lower combatant casualties).

Eight questions the world faces as lethal drones proliferate

But there has been insufficient attention, both within the government and from NGOs, in assessing the broader-view net result of the drone program; said differently, and channeling former Secretary of Defense Donald Rumsfeld, are we killing more terrorists than we are creating? While effective at killing their intended targets, drones on the flip side have also been used by terrorists as a recruitment tool and can generally fuel anti-American sentiment around the globe, particularly in regions where U.S. drones fly (and strike) regularly.