The whole MIAC report debacle got me thinking about how a country's citizenry can bring down an oppressive state apparatus. I often surprise people when I talk about gun rights, because I don't focus on hunting or self defense; the single most relevant issue is that the ownership of guns by the common citizenry is the final defense against totalitarianism.
We talked about this issue at a College Libertarians meeting a while back (I'm the sitting President of Pitt's College Libertarians) about the topic considered from this angle, and some people raised some compelling objections. Essentially the argument went "you seriously think we're going to fight off tanks and aircraft carriers with shotguns?" Now, there are historical examples of people using armed resistance fairly effectively against a vastly better-equipped and much larger force. The countries occupied by the Nazis in World War II did it with some success, for instance. However, I'm willing to concede that as strategies go, armed resistance is questionable on both moral and practical grounds.
So if armed resistance probably isn't the best option for bringing down a tyrannical government, what would be better? The best work I've ever found on the topic is a book called From Dictatorship to Democracy: A Conceptual Framework for Liberation. It's available for free online at the Albert Einstein Institution's website. The single most important observation its author makes is that by engaging in violent resistance, citizens are choosing the field on which a dictatorship is best equipped to deal with them, and that a more sensible plan would be to attack where dictatorships are weak.
I don't want to go into the details of the book, but I do want to remark that it's apparently been effective. The text was a key tool to the groups that brought down Milosevic.