China doesn't want to fight wars that are damaging to them. They don't declare open war and do it head to head. They want to get to their objective, not suffer damage. There's also a tribute system, where you have more power and then you have more hierarchy, and everyone should know the hierarchy and the lessers should give tribute to the greater, and the greater should respect that and they should work together.
The Western Powers in history, when they fought the Chinese and the Japanese, were stronger at it because they had practice fighting.
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We can really contrst Thailand with Myanmar.
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