The question is, “How many looters should the Guardsmen kill?” They are trained soldiers, not cops.
If they are sent in unarmed (or worse, with empty weapons) they are being set up as targets themselves. If they go in locked and loaded, somebody is going to alarm a soldier and all Hell is going to break loose.
“How many looters should the Guardsmen kill?”
Every one they see engaged in looting businesses or burning property down until it stops. Rioting is a very serious breach of order and should be treated as such.