The alternative is the CCP being a constantly increasing threat to the entire world and pushing us towards an increasingly authoritarian dystopian future.

Okay, China is dead. Destroyed. Nuked into oblivion. No more China, no more CCP.

What the ever-loving fuck is the next step in this scenario which doesn't result in massive backlash against the US and the ideology it champions and a surge in the fortunes of the Soviet Union?

I am a consequentialist. If we can create a proven better future with more happiness and security then bloodshed is not just optional: it is necessary.

A big part of my point is that what you're proposing is not only not a proven better future, it is a likely worse one.