Earlier quoted context omitted.
Then you really lack perspective on what any warfare is: it's always critical, life or death decisions that have to be taken without sufficient information. US civilian to combatant casualty ratio in the recent conflicts have been significantly better than any other modern wars as well. So, what do you suggest instead?
Have we considered maybe _not_ killing them?
I would be more concerned with the classification of any male over 16 killed in a strike as an automatic combatant than a single given operation gone wrong. This is an unavoidable aspect of war.