And unless they're veterans of the Korean War, the combat vets are learning for the first time what fighting a modern conventional army looks like.
Guys who have been in Iraq and Afghanistan haven't seen anything like this.
That is what the fleeing survivors are telling.
But they have see a lot of intense, brief firefights and a lot of cat and mouse mutual hunting.
I suspect the latter actually comprises the bulk of the fighting as both sides are quite dispersed.
But they will never have experienced a heavy artillery bombardment, grad missile bombardment, or been on the receiving end of an armored assault.