The usual argument is that the guns come in from "outside" and if we could just expand the control all over "outside" it would get all better. Apparently it requires rocket science to understand what a load of bullshit that is
When it comes down to it, the drug cartels could easily become their own creators of arms and design an entire black market to arm both defenseless citizens ($$$) and their own troops.
Nothing like a home invasion when the bad guys *know* no one inside has any deterrent.... :P