This is a pretty good explanation:
I like the way that he highlights the hypocrisy of a government that keeps guns for themselves that it demonizes as having the sole purpose of killing as many people as possible in the shortest time. If that were true, why would the police or homeland security need them? Homeland security calls them personal defense weapons when they buy them, but assault weapons when citizens own them. And what about all the ammunition that homeland security is stockpiling? That duplicity should make your skin crawl.
Lesson learned? We’ll see.