>USG is under no obligation to have up to date information.

Why not? This is not the perspective of the various international agreements the US has signed about war. Knowing what you are shooting is in fact an obligation.

Hell, knowing what you are shooting is an obligation of deer hunters in my state. If you shoot someone because you thought they were a deer, you are in trouble even if they weren't wearing an orange vest.

The reason this obligation exists is because you always have the option to not shoot. If you do not know accurate info about what you are shooting at, you are supposed to not shoot at it.