Other options for political change:
1) About half the revenue for the federal government comes from income tax. So the poor could quit paying. Unfortunately, thats a fleabite coz they dont pay much, the fed reserve would write a check and it it would be lost in the noise. When the rich have a tax revolt, they notice.
2)Civil disobedience. Mebbe, but right now the seriously disgruntled are killing themselves. Dont see anyone out on the streels yet. Well, except the homeless and the panhandlers.
3)General strike. Wobbly city. People dont like starving, and most are a paycheck away from disaster. And little sense of community to bail em out, make sure they're still eating, except in the boonies.
4)external factors: china could sell a trillion worth of US bonds, and more important all the fannie,freddie and ginnie debt they hold and spike interest rates foraminnit until the FRB wrote some more big checks.
(For the record, i don't think they will, but they have already stated they wont accumulate any more. They dont need to. But the US needs to keep selling and foreign buyers were about a third of the market )
Or Japan. Or the EU. Quitting buying US debt would signal loss of confidence or equivalently higher risk rating to US gov secured debt than quoted rates. The usual response to that in our brave, new, capitalist world would be a black market in trading US debt below the face value, sorta like currency exchange in banana republics, where you get very different values on the street than in the official markets. That would lead to political change real quick, probably in the wrong direction.
We live in interesting times
sidd