This seems better to me than sending an entire generation of young men to die miles away from home. I imagine if a nations automated robot army gets decimated by another robot army they will surrender immediately rather than send their citizens in to get massacred.

Any nation with the capacity to build a robot army will also be socially mature enough to not want to commit robotic genocide against their surrendering foe. Although the current economic/resource subjugation that is done militarily might become more pronounced.