Almost all combat vets know that at times war can reduce the best of us to our most base, cruel, animal characteristics. Sometimes that can include killing anything you're able to reach.
But alas, we're supposed to be the good guys. Immune to those urges that driven soldiers since the group from Cave A attacked the group from Cave B.
Men at war often behave badly.
As a Viet Nam veteran I witnessed events that some may term "atrocities." Were the men/boys involved evil or amoral? Of course not. They were just people. Brave, cowardly, shy, agressive, loud, quiet, fat, thin, short, tall, regular people.
Why the revelations of this group should be special eludes me.