My impression is China doesn’t really have a lot of allies. They have Pakistan, North Korea and Iran. Their relationship with Russia is complex and they seem to want Russia more as a dependent vassal state rather than an ally. North Korea already is a vassal state, not an ally.
Meanwhile the US seems to have a lot of strong allies in the region. South Korea, Taiwan, Japan, Australia, New Zealand.
What about other nations in the region? Where do places like Indonesia, Malaysia, the Philippines, Vietnam, Mongolia, etc fall on the spectrum of military alliances?
I was under the impression that the Philippines switches back and forth between siding with the US vs siding with China.
If war broke out, would it be the entire region vs China and North Korea?
You’ll have to find out which of these countries the US has defense agreements with at the moment.
Frankly, I don’t think the US can expect any of those East Asia countries to come to its aid if we were directly attacked like we have with NATO. The better question is whether the US will come to their aid if they are directly attacked by China or one of its allies, and the answer is probably “it depends.”
Southeast Asia is kind of riding the fence. They all have reasons to dislike China but yet not fully embrace the United States or the West, and some, like the recent Rodrigo Duterte were known to deliberately try to play it both ways as much as possible.They also all depend fairly heavily on economic trade with China.
Vietnam in particular has centuries of strife with China, and would be relatively easy for the USA to lure over as an ally if Washington were to try hard to do so. The Philippines can’t afford to field much of a real military; they are American-friendly but defense has never really been on their mind except for dealing with occasional Chinese naval harassment and their own Muslim extremism problem in Mindanao. Indonesia isn’t really Western and has the world’s largest Muslim population, so, not very friendly to the West. Singapore is Westernized, but has too much of a Chinese population and economic ties with China to ever really be much of a US ally. I’m not sure how Malaysia feels. Meanwhile, Brunei behaves kind of like a tiny Arab oil state, except that it’s in east Asia.
The United States has bilateral security treaties dating back to the 1950s with Japan, South Korea, Australia, New Zealand, Thailand and the Philippines. We previously had a security treaty with Taiwan but that became defunct when we transferred diplomatic recognition from Taipei to Beijing. We have varying levels of defense cooperation with non-treaty allies including Singapore and Vietnam.