there's no war in pakistan... officially anyways.
so this was a police operation or police assistance operation or whatever the fuck - which made _no_ attempt to apprehend the suspects(no attempt at a trial, just a long range killing).
so yeah, he's not taking full responsibility. he knew that when he was saying it. he's not even taking war crime responsibility for it. he's not actually taking any actual responsibility for the act or ordering a hit that resulted in a dead american - or the others which have resulted in scores of dead civilians.
and quite frankly, you should already know that the drone hits are just call-a-hit's for local governments - they define who is a terrorist or not in pakistan, and those actual terrorists they don't want to whack they don't order hits on - they get to choose and USA gets the blame. yemen for example was using them for getting rid of political opposition figures(and now the whole country is a mess).