I've said it once and I'll say it again.
Better 150 muggings than 100 muggings and 25 firefights.
Also, a lof of anti-gun people in this thread as well as others don't understand that the second amendment isn't as much about defending yourself from other citizens, but rather defending yourself against the government.
Penn and Teller may be magic, but they're wrong. The people don't bear arms to defend against the militia, they bear arms so that they may form a militia. In order to provide "security" for "a free state." Obviously, against outside threats. The British weren't a militia when fighting broke out in Boston; they were an occupying force of reprisal.
You don't have security against your own government. You don't maintain a parity of force with body that rules you consensually. That's futile and dangerous. The state has a monopoly on the legitimate use of force. This is practically the entire definition of a state.
Americans have never taken up arms in defense of the Constitution even when it has been fragrantly violated by the government. We have fought a civil war, which would be silly to put down to an armed populace, but how freaking naive do you have to be to believe that an armed populace is something that deters state tyranny? That's just not how states and societies work, and it's not how history has played out.
What's more common? A government spontaneously deciding to massacre its own helpless people, or governments acting ruthlessly in response to ongoing conflicts that are only serious because the people bear arms?
It's not about guns. Guns are just a tool. I don't think anyone will argue with me here. A populace that resists the abrogation of their rights is a sociopolitical phenomenon independent of firepower. Most armed populations in the world today simply wage wars and cause strife without every taking up arms for ideological purposes. Either that, or they fall in line with their oppressive state because the machinery of government is well oiled, and do harm to foreigners.
So in conclusion, your delusions of heroic defense against Washington are misguided and sad. Wanna fight the power? Tell it to Somalia.
And the armed people form a militia because at that point the United States had no standing army, and they had hostile colonial powers and a dangerous wilderness that could pose a threat to ordinary people without menacing the entire state. The militia in this case is a tool of the state, but one which relies on the armory of the people. People aren't armed to resist it. Now that we do have a standing army, people with too much testosterone can fantasize about forming militias that will defend against it.