Since it got independence from UK back then. USA developed into a military nation. And thats why its partly a democracy, to ensure prosperity aswell as being the best around.
In Europe you have parties to pick from. If you wanna support green deal policies.. you can have a party for that. If you support social democracy... there is a party for that. If you support right wing politics.. there is a party for that.
USA you get two choices. Democrats or Republicans. And thats it. Sure there is green party politics but who votes for those anyways :P
Essentially the way USA is built up is to get few benefits selections "depending if you vote democrat or republicans" so you get a very polarized way of looking at things. Either you are team A or team B. Which policies do you support or dont support?
May have been done this way and may be formula to why USA is such a world super power to begin with. Not sure if that would buckle if it became a pure democracy like European countries are.
And thats the way it is. But i tell you one thing. I rather have USA as ally than authoritarian regimes like China or Russia. If anything i am a supporter of Hong Kong or trading with them, considering they are fighting for democracy in that area.