Please don't use this tragedy to justify aggression against others. If you really want to address "gun crime,"

1. Teach basic firearm safety to everyone
2. End the "war on drugs" to carve out the heart of the violent black market. Prohibition creates the atmosphere for crime to blossom.
3. Don't disarm your neighbors. The worst thing you can do is demand more government violence against peaceful people in the name of "peace."
4. Realize that violent crime has been plummeting in the US even while firearm ownership has proliferated, completely obliterating the preposition that guns cause crime.