Brother, I can talk dumb and ineffective gun laws all night long without repeating myself.
Problem is that people, of any political persuasion, don't get the notion of political capital. I rant about it a lot. :)
No matter how right you think you are, no matter how scientifically valid your reasoning, no matter how sensible, no matter what, making laws costs goodwill. Decisions cost votes. And votes determine one's ability to stay in office and effect the sorts of changes one, and hopefully, their constituents want.
Knowing that and factoring it in is what politicians need to be doing. FFS, this is high school Government 101.
Guns for example:
"We want a 'high capacity' mag ban!"
Well, none of that works like you think. High cap mags jam, the military won't even use 'em, only mass shooter idiots, and I'd rather their shit jam. Besides, swapping a mag is trivial for a shooter, 4-seconds if he sucks. Can we talk about it?
"Children! Safety! WANT!"
OK, it's gotta cost voters, and cost you a chance to make real changes.
"WANT!"
tl;dr If the Democrats had brains enough to read the room, they'd drop the non-stop gun ban shit, take the issue back from the assholes, gain all those single-issue voters and sweep the polls everywhere.
"WANT!!!"