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Let's say Japan (somehow) maintains a level of democracy comparable to the Taisho era and avoids going on an Imperialist rampage.

Japan's boundaries thus are the home islands, Southern Karafuto, the Kurils, Taiwan, Korea, and Micronesia.

How powerful would this Japan be in the long-run? This country likes has around ~260 million people I'd think. Growth may be slower due to a lack of US-imposed agricultural reforms, though Japan may reform itself on its own.
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