In an article by William Bennett, CNN, Dec. 20, 2012: Case
for Gun Rights is Stronger than you Think, Bennett makes the case that the evidence doesn't really show that banning guns increases safety. As he points out, most of the recent shooter incidents have occurred in places where guns were already banned, so the victims were unarmed even though the shooter wasn't. The 2007 shooting at the New Life Church in Colorado Springs was halted because an off-duty policeman happened to have his weapon with him and shot the intruder before he could cause any more damage. Would Newton have been different if the principle, who lunged at the shooter at the beginning (and was shot dead) had been armed instead? Perhaps.
In The Atlantic Steven Hill and Robert Richie have an interesting article Why America Can't Pass Gun Control in which they explain why, as a matter of political calculation, it is hard to get effective gun control. It all hinges on a small number of mostly rural House districts that are key for both Republicans and Democrats in controlling the House. These districts are solidly pro-gun-rights, so doing the "right thing" on gun control might also involve losing control of the House. It shows that this gun control issue is not nearly as simple as it seems on the surface.