There were some small Alaskan islands that Japan actually seized. The non-military population of Alaska in 1941 was tiny, about 73k, and land links to the lower

There were some small Alaskan islands that Japan actually seized. The non-military population of Alaska in 1941 was tiny, about 73k, and land links to the lower 48 were weak, so isolating and occupying the territory by sea might have worked. The same goes for at least the smaller Hawaiian islands. The Philippines were successfully occupied despite a much larger population. Regarding Asia, I think "to acquire territory" is not the real question. Most Americans today would say that we should assist staunch allies such as South Korea if they were invaded, without any desire to acquire their territory. That goes more for the Philippines in 1941, since the US had given them a 10-year security guarantee under the 1934 Philippine Independence Act.