One other thing, food for thought.
It was my infantry battalion (2nd Bn, 9th Marines) that intervened in the Rodney King riots in LA. To be fair, the CA Natl Guard did most of the heavy lifting. They didn’t get the credit they deserved. 2/9 was only in support; but the ROE allowed for deadly force.
Not completely sure of the legalities, but the California national guard I think had a right to use deadly force to suppress riots. I'm not sure the Federal forces could do so legally, but of course it's the government, so they can get away with it if they want to regardless of what the law says.