In an ideal world, an armed population would be able to protect themselves against crime. In reality, it doesn't work that way at all. The vast majority of people just lack the guts and skills to defend themselves, let alone others.
Where would you get the "vast majority"? Like to see some
statistics on that.
Sometimes private gun ownership even prods the authorities into action.
Remember those kooks in the Jordan valley of Montana? The ones
handing out their own version of money to pay taxes and bills etc? The ones who were cheating and threatening their
neighbors? The local
Sheriff wasn't capable of doing anything, the Feds weren't doing
anything,
so the neighbors said "We'll take care of it." Made posse's
and plans for getting rid of them. That forced
law enforcement to step in before they lost control.
http://www.adl.org/mwd/freemen.asp