Al, if you really don't have the answer you need to take up flower arrangement for a living. It isn't as if the LEOs of 38 other states haven't addressed this situation.
All of this "sky is falling" nonsense occurs every time the anti-gun nazis lose a round. They keep saying the streets are going to run red with blood...but it never seems to happen. Doesn't stop 'em from bleating, though, does it?
G-d, no kidding. The guy tells you he's armed and has a permit so you know about in advance, and you don't know how to react? Agreed, take up flower arranging, or maybe get a job at Krispy Kreme. And make sure they don't make you do any of that stressful counter work.