Indeed. It all depends on when the "didn't have any military overseas" happened. If the US just said bye-byes to Japan after WWII and pulled out, the Japanese Defense Forces would probably be several times bigger than it is today, to match the rise of the Chinese military power.

So would South Korea and Taiwan. Remember Taiwan had a mutual defense treaty with the US until the 1970s. Without that, there would be aboslutely no doubt that Taiwan would have invested a lot more than it did into its defenses. Perhaps even found ways to complete its nuclear program and become a nuclear-capable nation.

And Taiwan is considered a threshold nuclear state, with its nuclear program terminated only under US pressure. If the US had no interest nor involvement in Taiwan, then it's extremely highly likely that Taiwan would have became nuclear-capable as early as the 1980s.