A totalitarian state is prone to falling apart - the USSR is a prime example.

Long term, american bureaucrats stay in the government pushing for the same stuff for the length of their career. Even once they've retired, people like Robert Muller come back to put in bits of work.

Yep, as long as a "strong, smart" dictator is in power things can move along fine, but the second he shows cracks in his armor plate all the people he has fucked over, berated, imprisoned are waiting in the wings to take him down, and then you get instability. That's one reason China was able to survive. Although it's an authoritarian one-party country, the CCP was smart enough to eject the leader every so many years, they threw away that advantage with Xi and declared him dictator for life. Democracies are messy, but they can also be self-correcting by not letting power aggregate for too long around one cult of personality.

> A totalitarian state is prone to falling apart - the USSR is a prime example.

That's taken as an article of faith, but I'm not sure how true it actually is. Sure some totalitarian have fallen apart (the Soviet Union), but others have not (China), and Western liberal democracies aren't looking so stable nowadays.

Totalitarian regimes have a fundamental problem: succession. Very few empires cracked that nut.

Can you list the liberal democracies that aren't doing so well?

I'd point out Greece, Italy, Argentina and Brazil. I'm sure there's a no-true-scotsman argument to be had for each of them, but they're nominally considered democratic republics.

Looks like these bureaucrats hold a big chunk of the national sovereignty for someone whose not subject to a popular vote, and this job is for life?

I don't think is true when it comes to foreign policy objectives, especially those centered around energy infrastructure (oil reserves, pipelines, etc).

Consider policies around strategic alliances (Saudi Arabia, Israel) and regime change (Iraq, Syria, Iran, among others) from at least the 90s through the present day.

The US has a presidential position that is too strong (the US-type presidential system is often called one of the worst US exports) but there are long established institutions and mechanisms that keep the ball going. Trump(ism) found gaps and there are enough holes to make a mess out of things like transfer of power, but it's what keeping America from falling apart.

Remember JFK, transfer of power after Nixon, even the Bush/Gore debacle. The whole machinery worked in the end, however flawed.

Totalitarian regimes like China, where you dismantle your opposition, including state institutions, make them very vulnerable. If Xi or Putin disappear tomorrow, there would be utter chaos.