There is a simple solution to this problem. One that has already been used effectively. A concealed carry permit, a .45 (or whatever caliber you prefer), and the willingness to use it. A young punk in Detroit came down with an acute case of lead poisoning after he tried to play with the wrong guy. If that happens a few more times, these little punks might get the message. Unfortunately, it won't help in NYC, DC, Chicago and other cities with strict gun control laws.