Back in 2002, the so-called Washington-area snipers went on a three-week killing spree using a Bushmaster AR-15 that resulted with ten people dead. On December 14 of this year, Adam Lanza used the same weapon to murder twenty children and six adults in the Connecticut School Massacre.
Good guys need guns to protect them from the bad guys. If guns were criminalised, only criminals would have guns. But even if Adam had walked through the front door, the security guard would not have been able to stop him with his puny hand gun. Unless the good guys are going to pack the same amount of fire power as the criminals, they will always be at a disadvantage.
These assassins are psychos who don't care about other human life or their own. They are like suicide bombers. The right to own a gun was never intended for these people. It is a whole lot easier to stop the manufacturing of dynamite than to stop the bomber from lighting the fuse. If pro-gun supporters want to keep their right, maybe they should push for regulation to keep gun ownership as safe as possible. If the sole purpose of a firearm is mass murder, it should be banned from civilian ownership.