>They're focusing on this and not, more militarily focused war crimes, like killing POWs

This first sentence shows you don't know whats happening. Kidnapping these children is a form of Genocide. The take these kids back to Russia, raise them as Russians and the kids will forget about their parents and their homeland. What they have done is sinister to the nth degree.

Don't get me wrong, obviously killing POW's is a war crime, and is despicable. But killing people who (generally) sign up for war is much different than brainwashing innocent children.