I'm not for limiting gun ownership; I stated that several posts back, but I can't see how banning guns will make them more pervasive...
Guns aren't like liquor, they can't be make by John Doe in his back yard; perhaps if guns were banned a few more gutsy criminals would use some leftovers to rob a store, but they don't last forever, and when one needs a need one or more ammo, he'll be buying them for inflated black market costs. I would bet most average law-abiding Americans don't have guns to use for defense anyway; I don't and only one or two people I know do, and I live pretty deep South, so it doesn't make much of a difference...