That argument is very poor because it assumes that (1) pacification has so far failed for lack of proper motivation of service members, and (2) bringing their f

That argument is very poor because it assumes that (1) pacification has so far failed for lack of proper motivation of service members, and (2) bringing their families in possible harm's way will properly motivate them. You haven't demonstrated (1) and it disregards movitations such as a desire for advancement (higher ranks), or not getting shot at (lower ranks), and (2) can have many outcomes (there are faster ways to get home for an individual than winning a war), the least probable of which is the outcome you "guaranteed". You're merely appealing to emotion while simultaneously disregarding all other (and much more relevant) factors leading to a drawn-out war.