[Faceman]

Yes but there's a difference between a battle axe and an axe to chop wood akin to the difference between a hunting rifle and an SMG.
The problem is that SMGs are designed for carrying out a specific action (i.e. shooting lots of bullet in short time at short range). Whether you've got a lawful reason to do that or not, if you fire an SMG you are using it in a manner appropriate to its design.
Would you say that somebody who's driving his Ferrari down the highway at 150mph is MISusing his car? No he just handles it appropriate to its design. The fact that he acts unlawful does not enter into it.

And after all that it still stands up, that guns are the most effective personal killing tool nowadays.
Again I emphazise: I'm all for self-defense. If somebody needs a gun for protection he should have one. But I think one should be aware of the great responsibility one carries with that. If you buy a tool for killing you acknowledge the fact that someday you may have to kill somebody with it. This may be pragmatically cynical but if you decide for having a gun you should have the stomach to say: "I will shoot if you break into my house" instead of "I use the gun for fun, it's nothing else but a fun tool like a car" because it isn't.