"Historically, those whose ideals proved a threat to progressivism found themselves in mass graves."
-Tasso Rampante - Commenting at Uncle's
That, my friends, is why gun ownership and the carrying of arms is so opposed by "progressives." One of the key tenets of progressivism throughout history has been to force others to live under their utopian ideals. Control is essential to the progressive notion of "progress" and thus, the autonomy, self-reliance and freedom of individual gun ownership is the ultimate threat to their stated goals and their ability to gain and retain power. This is why "progressives" have historically disarmed the people.
It's a hell of a lot harder to force people to do what you want when they retain the ultimate means of saying "NO!," the ability to kill your ass if you fuck with them bad enough. A "NO!" carries far more emphasis when there's a rifle in hand to back it up. The British learned this first hand, and even the most intellectually challenged anti-gunners understand it at some level.
H/T to Sean for providing the impetus for this post. Make sure you go read.