Bret Stephens: I know we’ll have to bring this conversation around to the Twitter feud between President Trump and Senator Bob Corker. But I don’t think we can begin with any subject other than Las Vegas. Everyone seems to want to understand the murderer’s state of mind. That strikes me as largely beside the point. What do you think?

Gail Collins: Bret, you wrote an amazing column last week about repealing the Second Amendment, which would certainly do a lot more to stop mass shootings than psychoanalyzing the gunman. However, since that’s not going to happen, I do find it useful to at least try to figure out what creates this kind of person.

Bret: No doubt we’ll find out more about Stephen Paddock’s state of mind as time goes by, but perhaps the most noteworthy point about him was his utter normality. Even his reported use of prostitutes and supposed remarks about being “born bad” are just, well, relatively ordinary bad male behavior. He was the “banality of evil” incarnate.

Conservatives often say that the way to stop mass shootings isn’t by limiting access to weapons, but by doing more to make sure mentally ill people don’t get their hands on them. It’s a weak argument. For starters, even the most competent government agency would be hard-pressed to spot and stop deranged people — whose dark fantasies occur in the proverbial dark — before their rampages. And then you have these same conservatives block efforts to stop crazy people from purchasing guns on the grounds that they mustn’t have their Second Amendment rights removed without due process.