Gun freedom is the only thing that stands between us and complete tyranny.
I’ve never been too sympathetic to this viewpoint myself. I don't have a problem with civilian gun ownership, but not for that reason. In my opinion, if it’s come to threatening to shoot or actually shooting agents of the Government, then it’s too late. In examples where people have used guns to stand up to the Government in the United States in recent times (Ruby ridge, Waco, ect) they’ve lost. If the machinery of Government is turned against a private citizen or even a group of private citizens, they cannot win by force. Empirical evidence also tends to bear the collorary out – many countries with very little gun freedom (eg: Japan) are not tyrannies.
Personally, I tend to think that freedoms are safeguarded by vigiliance, informed participation in the political process and working to change the Government from within rather than opposing it from without.
Japan is an exception (for now). It's really their culture and the type of people they are that makes it generally peaceful there. On the flip side, their social mentality could give rise to a very terrible tyranny, accepted by most citizens, if the wrong people got into influential positions. It's just the way they are.
If you read the constitution of the United States, it isn't supposed to have a standing, "professional" army. Every two years there's supposed to be a process (vote, review, I can't quite remember) to determine whether the official army stays or goes. The Navy is maintained due to the need of maintenance on vessels, and in the modern day I assume the Airforce would be maintained as well - though neither of these special branches would technically be "active." Doesn't seem to be working that way, eh? Nice to know that your military exists illegally, right?
Basically what I'm saying is, "the machinery of government" as you put it, at least in the United States, shouldn't even exist. The civilian shouldn't have to worry about fighting their own army, because that army shouldn't even exist! And then we get into the whole matter of weapons-control. Even if there is an illegal, standing army, civilians should be just as well equipped as that army. I should be able to legally own stinger missiles, HE, or even a tank or fully-armed F-4 Phantom if I wanted to (and had the money).