The idea that the American people could make an armed stand in conflict with the US military is about as foolish of a notion as can be dreamt up.
Please refer to Vietnam and Afghanistan.
An armed uprising in the United States would be a terrible, horrible outcome for all involved, but it certainly would not be easily crushed.
The point of being armed is not to rise up against the government, it's to make government abuse on a small level more difficult, risky and costly for the government than just not acting like jerks in the first place. By greatly occasional abuse it's much harder for abuse to become more normalized.
The Waco Siege is a good example. If those people hadn't shot back there would never have been a standoff, the media would never have shown up and the public would never have been able to scrutinize the government's actions.
Another example is police no-knock warrant abuse. In places where many people have the capacity to shoot at you if you kick down their door in the middle of the night the police generally don't abuse no-knock warrants because everyone knows that if you hand them out like candy you'll eventually get a dead cop and public scrutiny. In places where the vast majority of people cannot shoot back you see all sorts of sloppy behavior (e.g. swat team kicks down a door based on a driver's license address without even checking with the landlord if that tenant is still renting that unit) because the risk of abusing people like that is low.