Man liberals are delusional on guns. Every time they try to win this fight they lose hard in the midterm. Yea Hillary has a tough gun agenda and will run with it in the general but I doubt she'll focus on the issue as the nominee.
Liberals tend to create a moralizing bubble in which they repeat the same emotional arguments to each other without realizing the public has other concerns.
James Taranto has a theory that Democrats have a largely friendly media that they associate with which harms them by not challenging them on subjects they agree on like gun control. Which leads to the assumptions about how everything's just a messaging problem.
One of his concerns is that Fox, talk radio and stunts like the debate complaining is slowly creating the same bubble for Republicans to their detriment as they no longer have to defend their policies on hostile ground.
I think there's some merit to the argument, and definite merit to the consequences of the premises being true.
And I also think it contributes to the polarization narrative, where both parties believe Americans agree solidly with them. When in reality, Americans by and large agree with both parties but not necessarily on the issues the parties think they do or to the extent or specifics, especially the parts of the parties within the bubbles. Gun control and abortion are often good examples of this.
I think part of the Trump denial stems from this. The media and establishment in general among its many arms, the parties, think tanks, "political experts", etc. are struggling to understand his appeal, and his increasing appeal, including in the head-to-heads with the felon Hillary, where he's no longer getting totally vaporized.
And it's mostly because they immediately dismissed him as "not serious" and so-on. And so the assumption is that things will "return to normal" and Trump will disappear. It's also why they continue to treat Jeb??? as a serious candidate when the GOP base has despised him for a while and he's clearly all but dead campaign wise currently.
There were similar sentiments among the elites regarding Reagan until he nearly beat Ford and then trounced Carter four years later.