Your impression is incorrect. Anything up to and including lethal force is authorized depending on the circumstances. Since NONE of us here knows the circumstances (including you) you'll never find out here on the interwebz why it happened.
Of every one hundred men, ten should not even be here. Eighty are nothing but targets. Nine are real fighters, and we are lucky to have them, for they make the battle. Ah, but the One... One of them is a Warrior... He will bring the others back.
"Wrong door, buddy!"
Let no man's ghost say my training failed him.