I got one reason and it’s a real good reason why the big boys are never going to get in a big fight
Nuclear weapons
Do you want another good reason?
Intercontinental ballistic missile’s with multiple reentry vehicles( ICBMs with MIRVs )
This is why the Soviet union never gotten a big fight with us in the 70s 80s 90s this is why China and the US will never get in a shooting war
Wars between the big boys are all economic
The Chicoms however, would think nothing about losing a hundred million people in a nuclear exchange (thanks to Bill Clinton and Lorel for making their missiles actually work for $$$) if they thought they could then dominate the Pacific without the USN.
My uncle and others I know talked about the human waves they fought in Korea when the chicoms enteted the war. They had no regard for the losses they were taking whatsoever.
I suspect if the chicoms believe they are about lose the mandate from heaven they will go to war with Taiwan or Japan to prevent their decapitation from power and that would drag us into a shooting war rather quickly. The only way the communist give up power is if we can buy the upper levels off or they are killed. I don’t see a Chinese Gorby on the horizon.