Korea is a democratic Western nation, they host US military bases and fly F-35. Korean made phones are trusted enough that American special forces use it for some parachute jumpings.

Since when is East Asia considered "Western"?

I live in a Japanese city with a US military base and trust me, the only Western thing here are the few bars that cater to them.

Among the many definitions of "Western" is the original sense of "First World", encompassing members of the geopolitical bloc centered historically on the US.

Sources? It is the first time I see that definition, and sorry but it doesn't make any sense.

If the world splits into a China bloc and an American bloc, Japan would almost certainly join the American bloc, right?