I’ve not read deeply at all on the ethics of drone warfare but wanted to reflect after discussing it with some friends.
I see five concerns commonly arise when thinking about the ethics of drone warfare:
1.) collateral damage
2.) impact on local communities (psychological, emotional, physical, etc.)
3.) the military and national security fallout for their use
4.) whether drone usage is a rule-governed activity with proper oversight/accountability
5.) reliability of target intelligence
However, even if all five could be overcome entirely, my ethical qualms would not be put to bed. I want to add a sixth concern that speaks to this unease, one, in my limited exposure, I haven’t seen raised much:
6.) the proliferation of targeted assassinations
This is a concern I have with the traditional just war theory, in particular jus in bello. Yes, war is hell, but I for one don’t believe it’s entirely avoidable. I think there are acceptable justifications for going to war (jus ad bellum). However, as Michael Walzer and others have helped us to consider, we’re then plagued by the question of determining what makes for justifiable warfare.
To avoid a painfully long discussion, let me register here my concern for the justified killing of enemy combatants. I resist Walzer’s sharp distinction between enemy and non-enemy combatants for a few reasons. First, it isn’t at all clear that an official enemy combatant is more threatening than a non-combatant (especially with the technology we have). Second, I don’t agree that in fighting for a cause one forfeits her right to life. Third, in unconventional wars like the “War on Terror”, it isn’t at all clear exactly what makes for an enemy combatant. This third point is an especially sticky one when considering the practice of targeted killing.
That said, I would move to include that war must be fought appropriate to its end (an Aristotelian point). That is, war is fought to win, not to kill humans. It may be that humans are justifiably killed for the end of winning, but to kill humans without an superior end is to commit genocide.  That is a meaningful distinction for me, and if we can’t draw it I see no way to avoid concluding that there’s no real difference between war and genocide.
Thus my lingering moral qualm with the use of drones for targeted killing is not the technology per se but the very act of targeted killing. This concern remains even if all five of the above listed initial concerns could possibly be mitigated. My concern with drones is that they provide exceptional ease, proficiency, and minimization of risk of military lives in carrying out targeted killings. It seems almost inevitable, then, that the use of drones for this purpose will lead to a proliferation of the practice. I am concerned with this becoming an even more convenient military strategy.  Targeted killing, from my view, is an ethically suspect act even at wartime, and the use of drones for this purpose should cast the practice itself into reconsideration.
- A much more lengthy discussion is necessary to determine when, if ever, it is justifiable to take human life in war.
- There is some evidence that the procedure for determining targets is fraught with problems as well. Yet, again, even if this weren’t the case concern #6 remains.