When you say a gun is a just a tool like a hammer, you have to remember that a gun was a tool essentially built for one purpose. To kill things. Whether that thing is an animal or human.
Sport and recreational shooting is something that is secondary to this purpose.
I personally feel that statements such as a 'guns don't kill people, people kill people' are stupid. A gun has basically been designed to kill. If a gun was just like a hammer, people would go to war using hammers, not guns.
While I do not think guns should be completely banned, I think it is important that people remember guns can be dangerous if handled incorrectly. How many stories do we here about kids getting killed or injured because they were mucking around with a gun? I read about some poor girl that got her face blasted off by a friend because he thought the safety was on and pointed the gun at her face.
Heck I saw a video of a police officer who shot himself in the foot while giving a demonstration on gun safety to students.
I don't think the need for stronger education, screening and controls is necessarily a bad thing. I think as a weapon, a gun is very impersonal. It would become easier I think to detach yourself from the situation as a shooter, than it would be if you had to run down and knife a dozen or more people to death.
I do think this is a topic is one of the big ones that divides so many Americans. You seem to see a lot of vehemence on both sides of the issues.