Most people will know how violent they are, so when threatened a “Rittenhouse Response” should not surprise anybody including the perforated anarchists.
If you’re on the premises, arson, or attempted arson is deadly force in and of itself, and a claim of self defense would be reasonable. But don’t let that give you the warm fuzzies if self defense is attempted in one of the Blue cities.
In Los Angeles, DA Gascon would prosecute the victim, and seek damages for the antifa goons posing as “Jane’s Revenge”.