The only way the US could fall is if it lost some sort of huge war in a huge way and its territory was conquered/balkanized. Can't see that happening in the foreseeable future.
The parts of the US that are the angriest about such things are the same ones who consider themselves to be the core part of the country. Seceding would not help them prove any point.
Although if there was any chance of the US falling, say hello to the republics of Texas and California. (Pretty sure the US Constitution still allows a state to secede at any time. Come to think of it, if the US was balkanized by an outside force all of the states could secede to reorganize themselves in a way that hurt them less - keeping the farm belt together, etc.)
The parts of the US that are the angriest about such things are the same ones who consider themselves to be the core part of the country. Seceding would not help them prove any point.
Although if there was any chance of the US falling, say hello to the republics of Texas and California. (Pretty sure the US Constitution still allows a state to secede at any time. Come to think of it, if the US was balkanized by an outside force all of the states could secede to reorganize themselves in a way that hurt them less - keeping the farm belt together, etc.)