Think about your day. You have almost countless opportunities to murder tens, hundreds, and possibly even thousands of people every single waking day. And yet you do not.
Because, by and large, you are a mature, responsible, reasonable, rational, "civilized" human being who is cognizant of the consequences of his actions and the social contracts that bind us together.
So why do "gun control" extremists seem to believe you will suddenly, radically, magically, and murderously change simply because you happen to have a firearm strapped to your hip?