Not accidental, coincidental. They had lists of targets and next to each the level of acceptable collateral damage. Afghanistan showed very clearly where that kind of "ah fuck it" attitude leads: Somehow the German-occupied regions were much, much calmer than the US ones. Now you'll hear Americans say "yeah of course we took the hard tasks and left you the rest" but the thing is: Americans made it hard for themselves. Taliban actually once wrote an apology letter to the Bundeswehr, saying "sorry for attacking your convoy, some idiots of ours confused you for Americans".