Why is it up to the democrats?
Because they're the only ones imbued with the power to defeat legislation on behalf of the people who are not themselves members of the fascist cult, though most of them are so deeply in the pocket of fossil fuel interests that they need snorkels to breathe.
Are the us population inept?
Yes, and no. The people in charge of doing things the legal ways are REALLY into stopping people from threatening their power and revenue streams by any means necessary or unnecessary up to and including mass murder.
Even peacefully protesting against oil pipelines is illegal in most jurisdictions and considered TERRORISM in some.
Ever tried to attack a tank battalion armed with just whatever rocks you are able to pick up from the ground, Gaza style?
That's about the power balance between regular people and powerful people in the US when the courts aren't available. Often even when they are.