"Would these cowards dare attack a well armed populous? I think not! " -- SovereigntyOrDeath
You're too limited in your thinking, that "terrorists" would not do something in particular. Imagine your surprise when they DO it. Further, they aren't cowards, either, and you once again misjudge them.
So yes, they would "dare attack a well armed populous."
You have to remember that most of them are suicidal, so they don't care about dying and don't expect to survive the incident. And besides attacking "innocents" such as ordinary civilians and children even, they also attack police and military, both of whom are armed. Not fearing death makes them the ultimate enemy as they are "supremely focused" and have to be killed to be stopped.
It's not AT ALL easy to override the "Prime Directive" if you will: Self Preservation. It takes GUTS to do that (one reason suicide is NOT "the coward's way out" as ignorant people say -- it never HAS been).
But I do agree that a movie theater IS a place where one would want to carry...as are so many OTHER presently GFZs, most all are places where large groups of (unarmed) people congregate, which makes them such a high-value target to "terrorists" or your everyday garden-variety psycho-shooter as we have here especially in America. In a place where a bomb has been planted, being armed won't help AT ALL in that kind of terror attack, but for incidents that happen when terrorists conduct "mall invasions" (as they have in Arab/African countries) in-person -- shoot up busses of tourists/school children, attacking individuals in their cars, or simply round up people off the street and into a building (like just recently in Sidney, Australia) -- then being armed WILL help!
America isn't experiencing the regular bombings taking place elsewhere (yet, anyway) so our CARRYING should help is any terror attack here targeting citizens as they will be done by PEOPLE, not a bomb (YET, as I said). And terrorists are no less vulnerable to bullets than their intended targets are.
But I view criminals no differently then I do terrorists, so I am armed for either of them, as each needs the same response.
Anyway, when it comes to being armed in a cinema, I think fellow OCDO member (and fellow Coloradan) "Saxxon" would agree that one should. ;-)