Read the story - http://www.chicagotribune.com/news/sns-rt-us-usa-shooting-denverbre86j0am-20120720,0,6584688.story.
Now the question. Do you think that it was the gun that killed those people? Or do you think that it was a "mad at the world" person that killed them? Do you think that removing guns from the world reduces gun "related" crime? Do you think that a person who wants to commit a crime be stopped from getting a gun or another weapon just by the removal of legal arms? Do you think that making it harder and harder for people to legally own a gun makes it harder or easier for the criminals to get one? Is the removal of guns the answer to reduce the amount of crime that is in the world? Do you think this guy would have still done this if he didn't have a gun?