[Webstral]

I think the way around this is to leave Japan in charge of Japanese territorial defense. All US assets could be assigned to missions directly affecting Korea. Inevitably, the North Koreans would try to use their subs to intercept sea traffic in Japanese sea space. Soviet air reconnaissance would stray into Japanese airspace. Japan would get dragged into the fighting, though deployment of troops outside Japan might be too much to ask for. Still, a robust defense of the air and sea around Japan based on Japanese assets would be very helpful to the other allies.