When the PRC formed in 1949, they and the USSR were BFF. (Also, in 1949, the USSR detonated its first nuke.)
In 1951, the US wanted a single Korea with a US puppet dictator, and was about to overrun and overthrow the DPRK when the PRC intervened. General MacArthur said the only way to defeat the PLA was with nukes, but Truman said, 'The USSR has MAD. You're fired.' And the US settled for a 'draw' with the DPRK remaining in the USSR/PRC sphere of influence and South Korea as a US puppet state. (The PRC consider this a Great Victory over the US by the PLA.)
But those two BFF, the USSR and the PRC had a falling out over what the PRC call Zhenbao Island and the USSR call Damansky Island in 1969. Both claimed the island, and both were furious that the other claimed it.
Then, at the World Ping Pong tournament in Japan in 1971, some PRC ping pong players invited the US team to come to the PRC, the US team asked for and got permission, and Kissinger saw to it than President Nixon got invited. The PRC went from BFF with the USSR to BFF with the US. The unitary Communist part of the world was divided into two.
Naturally, the US plutocrats, who only earned 5 times the US average wage under Eisenhower, saw a way to get all their labour costs down to a few ¢ and their net income more than 500 times the US average wage! Great job, Kissinger!
But the PRC slowly went from a nation where most people didn't have enough to eat, where millions starved to death every year to a middle income nation where no one goes hungry. From a nation where more than a billion people slaved all day, every day on farms to a nation where all those farms are deserted. Work done by hundreds of peasants manually is now done by one engineer with high-tech agricultural robots. The old farmhouses are now vacation homes 'out in the country', since the farmers no longer need them nor use them, having homes in the cities where they have jobs that were, until very recently, 996 jobs: i.e., work from 9 am to 9 pm 6 days a week (but that's highly illegal now and the CPC is cracking down very hard, and set up a website 996.ICU where workers can turn in illegal bosses anonymously; they'll get the same pay and only have to work 40 hours a week, because the factories are earning too much profit and can afford to pay far more for labour).
It is obvious that what the CPC is doing to its workforce is highly illegal, they're going to give workers all over the world the wrong idea, so the US, which has been cracking down on Russia to prevent their every again rising to the threat level once posed by the USSR, is now cracking down on the PRC, as well they should be. What would happen if all workers all over the world started demanding the kind of treatment the CPC is demanding for all PRC workers?
But with the US cracking down very hard on both the PRC and the Russian Federation, they have, after many years, returned to their prior BFF status. Basically, the last three or so presidents have managed to undo all Kissinger's work.
So the US is working hard to provoke Russian invasion of Taiwan and PRC invasion of the Ukraine. Or do I have that backward? Anyway, doesn't matter, the US military just need a good excuse to put the PRC and Russia back in their place. US intelligence say that job will be far easier than Grenada and Panama, and the sooner the US get it done, the better.