It’s very understandable that Japan...South Korea...the Philippines...Singapore and other nations of the region would be scared silly of China...particularly with a Chinese puppet in the White House.
They could not defeat China in a nuclear war. They could make the cost of war to high for China to risk it.
Oddly in a nuclear exchange China would defeat Japan, Korea, and Tawain would be a loss as cental control of the communist party in Bejing would no longer exist. China would break up.