BS! His guns should have been seized according to due process—he was clearly dangerous, and precisely the kind of person whose documented behavior easily justifies the due process that should have been imposed on him.
That's a far cry from "yours tomorrow". Indeed, its apples and oranges. Every gun owner in the country should be furious that this killer had access to guns, because his behavior had already called for (at least temporary) forfeiture of such Rights—via due process...
Trump saying due process should come after the fact. That’s bullshit. I do not agree with that sentiment at all.