On the surface, a sensible person could be forgiven for accepting the idea that making guns hard or impossible to get will produce less violent crime. They could also be forgiven for believing the idea that if you have a room full of children who are throwing rocks at each other, the sensible thing to do is remove the rocks. But this assumes society is made up of children to admonish.
Organized interest groups are able to control a lot of policy making, even if most people in the unorganized public disagree with them.