There's a saying - "the market can remain irrational longer than you can remain solvent".

Even if there was some natural physical law that guaranteed that oppressive nations would eventually be overthrown/atrophy, there's definitely nothing that puts a bound on how long that will take.

And, as we've seen with Ukraine, war can break out more quickly than any of us think.

(also, if the social justice warriors in the West have their way, the US government itself would be overthrown and replaced with its own, authoritarian, but ineffective regime, long before a conflict with China would occur)