How many hundreds of people die in the US every year because of guns? Certainly more than 100.
Considering that (in USA) guns cause only 0,85% of the total killings per year and most of gun killings are due to attacks in the retarded 'no gun zones' I'd say it's worth it, in fact most gun related deaths are suicides and that's saying something.
Also I can't even express how flawed the logic is, because I'm guessing you mean the mass killings, and mass killings are almost always caused by illegal guns - those terrorists today didn't give a shit if their guns were legal, did they?
Sure, you hear about school sprees etc. in America all the time, because that's what the media want you to hear. You don't hear the hundred of daily cases, where a gun saves someone's life, because basic rule of media is that good news is never a good seller. USA doesn't have a gun problem, it has an attitude problem - somehow in 40s/50s for example they didn't have as strict laws as today, yet nobody went to shoot up schools and all.