Because some idiot shot up a New York mall with an - already banned - assault weapon / assault-type rifle / assault rifle, (or anything with the word 'assault' in it because police aren't saying what type of gun was really used), as many as seventeen percent of the dumbasses that read CNN think there should be mandatory security checks entering shopping malls.

Presumably this would be done with a large compliment of TSA-style federal screeners, because everyone knows you don't professionalize unless you federalize. Everyone should plan on arriving to the mall three hours early so that you'll still have plenty of time to get through security and get some shopping done before the mall closes.

Also anyone showing up to the mall with an assault whatever will be immediately arrested, because those are already banned in New York.

UPDATE: Say Uncle has more about the media doublespeak. The gun was bought right after the federal ban expired. But the state has a ban to pick up where the federal ban left off. But the gun isn't an assault weapon so it's not banned anyway. The gun was bought at a gun show. But a background check was done and no loophole was used. The guy didn't have a permit. But he wasn't required to have one any way.

So much for investigative journalism. Journalism 101: When in doubt about a gun, just say 'assault' whatever.