the leadership of one party has made gun control (focusing on assault weapons, first) as one of their political party planks. No one will rise to the candidate level in that party, under its current leadership, without embracing and supporting those ideas.
the other party assumes our support because, realistically, we have no other place to go.
PART of what got Trump elected was the ABH factor (anybody BUT Hillary). If you don't want more (and more restrictive up to actual confiscation) gun control, the choice today, seems to be "Anybody But a Democrat."
Which doesn't mean the Republicans are our friends or staunch defenders of our rights, either, just that they aren't AS focused on gun control as their opponents.
One of our problems (and yes we did create it) is that we have, for a long time, been electing people to LEAD us, instead of REPRESENT us. And we don't get to pick and choose what they do, we only get offered "package deals" which ALWAYS contain some things that are bad, along with some good.
I think its wonderful that the Dems have taken the gloves off, and are no longer pretending to be our friend on gun rights so they can stab us in the back when we're looking at something else. I think in an open "Stand up" fight they will lose. Of course, I'm just one of the deplorables in the basket, and not worth millions of dollars, didn't go to the right schools, and don't play their game their way, so what do I know?