It's also true that only 16% of mass shooting use an "assault weapon", so it's pretty clear the end of the ban isn't responsible. Something that actually has a chance of passing through the Senate and would be way more effective is raising the legal age for firearms to 21, banning domestic abusers from owning firearms, and better background checks generally. Getting this passed would be a lot better for the Dems than vainly struggling to get assist weapons banned before either the senate blocks it or the Supreme Court overturns it. People say that it's not either or and if that were the case I wouldn't mind democrats wasting time pursuing an assault weapons ban, but in practice the democrats only have so much political capital and they seem to be ignoring other reforms.