I don't agree with you, personally. I think if there were serious risk from a militia the government could just shut off their food, water, phones, electricity, internet, gps, etc. and watch active militia starve to death, or they can bring in their tanks and bombs etc. The USA has so much of a military advantage over foreign nation's militaries that the only way a dictatorship gets overthrown is if the military says so. No significant support would get in.

Even during the American war of independence the majority of the fighting was done by paid regulars needing good logistical support. If Britain was connected by land to the colonies (and thus not needing to send their troops so far, and not as willing to give up the fight so easily) it would have been an easy win for the monarchy.