I think US people are incredibly naive in thinking that they are going to oppose government military action with their personal guns. It won't work, the only difference will be many more dead.
And if we're talking about a civil war or insurgency within US borders: An army fighting on its own soil and against its own citizens is surrounded on all sides and can't maintain secure supply lines.
Guns work. "Political power comes out of the barrel of a gun", said Mao.
(independent of whether you think the Bundys were in the right, the fact is, armed ranchers did deter armed BLM intervention, basically indefinitely)