#the US doesn't really have *any* political parties with the institutional capacity or organization of the CPSU

[tanadrin]

A lot of the mechanisms of Soviet collapse really have no parallel in the US government or economy, just because the systems are very different. A United States analogous to the Soviet Union would be a one-party dictatorship like PRI Mexico that had been experiencing decades of stagnation since the most recent global economic shocks (perhaps like modern Britain, but even more extreme), which is more diverse on the national level but with clearer geographical groupings of ethnic minorities (and where administrative boundaries at follow the major ethnic divisions,) and where every NATO country only maintained its NATO membership because the the US was willing to roll tanks into their capital cities if they didn't maintain similar authoritarian one-party governance.

Heck, when I put it like that, it's a wonder the Soviet system managed to last as long as it did!