http://en.wikipedia.org/wiki/Bonus_ArmyIn the spring and summer of 1932, there was an opportunity. 43,000 protestors had set up a Hooverville in Washington DC, to try to extract from the government their bonus from ww1, which was not scheduled to be paid until later. They needed it because they were literally starving..
Keep in mind that this was before the election of FDR.... Hoover was still President, and it was nearly three years after the initial crash of 1929. So, people were pretty ticked off.
Enough got to be enough, and the decision was made to break up the protest. The army was dispatched, led by Douglas MacArthur, and his right hand man, George Patton. Dwight Eisenhower was also present at the time.
At one moment, the US Army was assembled to attack their own veterans, it would have been quite possible for MacArthur to swing his army around 180 degrees, get the support of the veterans, arrest Hoover, and seize the government. The people out in the country were sick enough of Hoover to let him do it. Why he didn't will remain one of the mysteries of history. Surely being a thinking man, MacArthur knew there would be problems. Problem #1: Even if you do arrest Hoover, then what? Can you plausibly and legitimately operate the government, bureaucracy, collect taxes, and everything else that comes with it? I suppose it's do-able. Anyway the argument could be made that MacArthur was going to run for President himself at one point and thought he could win the legal way.
Eventually they violently and brutally cleared out the hooverville (Patton, the war hero, led the charge against the starving veterans), dispersed the protestors, and the outcry was such that FDR was elected and the Bonus Army was eventually given their bonuses early, and a lot of them were involved in working on the famous bridge project down in Florida when the WPA was started.
Anyway, here is what it will take for the revolution to actually happen. Keep in mind that it is perfectly plausible for just part of the nation to be in revolt, and a lot of it still trying to hold together:
a. Starving children. Right now, there are about 12 million children in the US receiving some sort of food stamp type aid from the goverment, out of about 80 million total kids in the country. You take that away, and 12 million moms hit the streets. The moms hit the streets, and then the dads hit the streets. The doomers can speculate about ways that this could take place, through economic distruption, food production issues, or whatever.
b. A factionalized military. In most of the revolutions, I am thinking Iran in 1979, Russia in 1917 and 1989, the USA in 1860, Germany in 1930, and any of a number you care to name, the turning point happened when some if not all of the military turned out for the rebels. Musharraf, of Pakistan, Moammar Khadafi of Libya, Robert E. Lee of the CSA, and George Washington of the USA are more examples of rebelling former or current military officers that was able to control a faction of the military.... Note: Right now, because of the "all volunteer army", the US military is as factionalized as it has been since 1865 because of the development of a "military caste" ...with a strong Christian Fundamentalist undertone extracted from the rural South. This has been well documented by various sources. At some point, in a revolution, the military is called on to fire on its own people.... and at that point, they have a choice....
c. Emergence of a charismatic leader, by whom, through the force of their personality, an alternative to the status quo is embodied. History echoes with these names, of course. Lenin, Hitler, Mao, the little chick in the Phillipines, Aquino, Walesa.... Boris Yeltsin? Maybe. we can go on and on. Naturally the leader is vulnerable to assassination ref: MLK...or arrest ref: Mandela. It is helpful for there to be an incompetent/doddering/corrupt leader to rebel against: In Iran, it was the Shah. In Germany it was Hindenburg, in Russia it was the Romanoffs. In the Phillipines, it was Marcos. In Cuba it was Batista. In Great Britain, it was King George III.
d. A competing ideology; In Iran, it was Islamic Fundamentalism. In Russia it was Communisim in 1917 , and then, in 1989 it was Capitalism. In Germany, well, we all know that one. It is helpful to have both an ideology and a charismatic leader at the same time. An argument can be made that there was one developing in the middle east in 32 AD, but the leader was assassinated before the military could be turned, and nothing much ever became of it.
d. Compliance, if not support, of the aristocracy. This is not 100% a reliable indicator, because of course there are plenty of instances where the revolution was explicitly against the aristocracy, but in a lot of the South American revolutions the rebels have at least the acceptance if not outright support of one faction or another of the wealthy in the country, who see the writing on the wall and consider their own hides to be safer with the rebels versus the guys in power.
f. A trigger event. History echoes with these names too: Harper's Ferry, The Reichstag, The Boston Massacre, Surely we can think of some more. Some event that ticks so many people so far off that they take to the streets. The Rodney King beating and subsequent riots are a prime example of a small scale incident of this type.
So there are at least six key factors, and I am ready to say that #1 is the most important, in terms of the likelihood of a place to go up in flames.
I can think of at least a couple of revolution scenarios that could work, at least regionally within the US. With a little encouragement I will share them with you.