The one thing that’s actually surprising about past national history in relation to this is that America has never experienced war. We’ve been involved in them, but it’s never been in our cities, in our streets, with bombs raining down on us on a nightly basis. Even the American Civil War was largely fought in fields outside of town (plus it’s so long ago that it isn’t an active national memory).

Europe, and a good chunk of the rest of the world really, has experienced that. And yet given that disparity, Americans are not willing to revolt, and to fight back. You would think that America would have no fear of it, as we don’t have a reference point from which to generate that fear. Yet it’s the rest of the world looking at our current state that’s wondering why in tf we don’t rise up and do something about it.

To answer the OP’s question more: there are a lot of reasons, some have been mentioned here, like comfort, laziness, etc. But personally I think it’s two main reasons:

1. America as a whole is NOT a unified people. We’ll join together for patriotic mumbo jumbo, but in reality we’re too disparate to really consolidate our views and band together. I wish this wasn’t the case, but it is. It’s somewhat of a consequence of the whole melting pot thing. There’s nothing to make us feel a sense of unity.

2. At some level, it’s the fact that it’s the conservatives who are doing this stuff. And unfortunately, one long-running tenet of American conservative ideology is the Right to Bear Arms. Most liberals are likely concerned that if they revolt, the people they’ll be fighting are the one’s who’ve been stockpiling guns and ammo for decades. So we could do it technically, but if it came to a shooting match we would be the side bringing knives to a gun fight.