Citizens have always had a right to protect what is theirs personal private property. They register their weapons and historically have taught gun safety to family and friends. There has been an AR-15 and a 45 glock in my parents closer since before I can remember. Yes, I touch it but never did anything more than moved from the closet or move it out of the way. I've known about them for 15 years and they have never been moved out of the closet or their room or used but some poor soul is in for a surprise if he/she breaks in.
The criminals get their weapons use them on a regular, vandalize and kill and obtain them illegally. Banning weapons will only increase their street value and promote more violence. And now, the people who would have had a gun for protection are weaponless.
I hope to God I'm never in a situation where a gun could save my life. But I am 100% sure that if it was a known fact that 1 in 5 people you meet had a gun and was trained with its use, crime would go waaaay down.