Policy is all about dealing with things that are within your control.
Guns, at least in theory, are things that can be regulated through policy. Unless there's some "Black Mirror"-style device out there that I dont know about, the human actions of 330+ million people cannot be legislated out of existence.
In my state, the one where this event happened, they don't do deal with the things that are within their control (often rescinding regulations, in fact), while paying lip service to the things they can't.