That's exactly my point, Doug. People already know that, but they go ahead and try to rob the store anyway. Knowing that one of the other customers in the store might be a retired cop with a gun isn't going to be any more effective in making the guy say, "Hey, maybe I shouldn't try to rob this store," if he was already dumb enough to try.

Or maybe you're trying to say that if an armed teenager walks into a 7-11 and the clerk pulls out a gun, then the clerk may have deterred him from completing the robbery. Sure, if you're defining deterrence in that narrow sense, you're right. But I think it's likely that one or the other of them will be deterred from carrying out his plans (robbing the store or managing the store) because he'll be injured or dead. I don't consider that a desirable result. And I would also submit that it's not going to deter the next teenager from trying the same thing--which, in my mind, is what deterrence is supposed to be about.

Nice to see you back, by the way. I'm now one state (and one ocean) closer to you...and I was in Tucson last month, for a teaching by the Dalai Lama. Beautiful country.

Aloha,
Mark