http://edition.cnn.com/2016/06/22/politics/john-lewis-sit-in-gun-violence/index.html
First reason for maintaining current state about gun is to protect gun manufacturers.
Second reason for that is American culture that they are entitled to protect themselves by gun.
The first reason is not worthwhile discussing. When it comes to regulate illegal drugs, are there anyone who insist necessity to protect employees of gangs, who transact those drugs.
My opinion for the second one is true as long as they can keep moral. Judging from gun abuse rate in the United States, can we say that?