I don't think the US military intervention in Afghanistan was well-directed in terms of attacking those responsible for 9/11. Nor do I think the ongoing operations are doing much to improve US security. Indeed, the wider "war" on Islamic extremism ("we must bomb Kobane into rubble, to save it") is likely highly counter-productive and bone-headed.
However, set that aside, let's assume militant Islamic extremists are justified military targets.
Are double-tap strikes justified? How can it be justified to bomb and kill rescuers of whom nothing is known other than that came to rescue people - they may be passing good Samaritans, neighbours, etc.? Answer: It can't be justified, and it is in fact against the laws of war.
How can it be justified to deliberately bomb funerals, which will draw people of lots of different types of association with the original deceased? There would be many men and boys who are there because they were family (near and distant), kinsmen, neighbours, acquaintances, random observers, etc. - *not* militant extremists.
How can it be justified to deliberately bomb militant extremists at home? Afghanis live in large family groups. Targeting them at home kills their parents, grandparents, brothers, sisters, cousins. You can only justify this if you have absolutely no regard for civilian Afghanis (and from your earlier comment, it seem you have little regard - despite your faux concern for women there).
Home compounds were targeted simply because a militant had spent a night there. However in Afghan culture (deriving from Islamic teaching) you are required to give hospitality to strangers, and it is not uncommon for this to happen. Random families have been wiped out for no reason other than that some "brave" drone operator watched a *suspected* Taliban stay at that house some night before, and so they get bombed another night.
Here's the thing, if you can justify the above, then tell me how you would be any different from a terrorist justifying attacks on civilians in a democracy? Certainly, if you can justify bombing militants' homes, then "terrorists" can equally justify shooting off-duty soldiers or bombing their homes - if it's not terrorism when done by western powers in Afghanistan, neither can it be if they do it over here.