The AIs understand "stakes" just fine. They just understand them correctly, without human emotion getting in the way. Humans place an emotional value on other humans, even if they're the enemy. Computer algorithms don't. They calculate in cold hard numbers, optimizing for the lowest casualty count on their side for the least cost and effort. Casualty count on the enemy side, if it factors in at all, is a lower priority than reduced casualties on the computer's side.
Yes, that's horrifying. Go ask some first responders about triage at a major accident scene. They have to do much the same thing when the injuries are more than they have resources to manage.
Cyanide safety training at a mine: "When the cyanide alarm sounds, leave the area. Do not stop. If you see someone down, do not stop to help them. Not stopping gives the rescue teams 1 person they know to go in after because you told them. Stopping gives them 2 people to go in after, except they don't know that because you're down and dying of cyanide exposure and can't tell them.".