The problem with this argument is that it misses the 'fact' that ex-felons having guns is not any more of a problem than 'good citizens' having them. The problem starts when the ex-felon has one and the good citizen standing next to him (or her) doesn't. I can see no reason why anyone not currently in jail or prison should be disallowed from being armed. Moreover, Columbine would never have happened if guns were as ubiquitous as they were meant to be by the founders, because the type of abuse that supposedly precipitated it doesn't happen in polite (read 'armed') society.