The logic is that Japan is the only country where one dynasty has continued uninterrupted since ancient times.
Of course, since it is not “nation = dynasty”, it is a very narrow-minded and arbitrary dogmatic logic.
Since Korea, China, and Japan have all experienced the collapse of their governance structure and loss of sovereignty at least once in modern history, there is no country without a historical break.
Rather, based on the current system, Japan is the latest country to be created, followed by Korea (1948), China (1949), and Japan (1952).
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