They operate on the zero-sum game superpower mindset just like the Soviets of old, that they cannot have their own security until their bordering regions are made up of vassal states or they grab enough buffer zone land.
In our context it is Mao's "palm and five fingers" where Tibet is the palm and 5 fingers are Ladakh, HP-UK, Nepal, Bhutan, AP.
They want to grab the whole Himalaya mountain range or Finlandize us where we become ((( neutral ))) so as to not antagonize them like how Finland was with the USSR
US works on a similar principle but they make sure that the neighboring countries of their adversaries become their vassals