> If the US Federal Government decided to bomb San Francisco, I'm not sure who exactly would be able to render the consequences.

true, but only vacuously so. the "US Federal Government" is not some monolithic entity with a single will. it is made up of many organizations, factions, and individuals with their own motivations. if a military official ordered the bombing of san francisco, their subordinates may simply disobey them. if the orders were actually carried out, there would likely be other parts of the government that would find it politically expedient to hold those responsible to account. they may or may not be able to direct the use of force to do so.

the government can only take extreme actions when some level of internal consensus (or at least apathy) exists, as in the case of the MOVE bombing.