I read this book called Tokyo Underworld, which covered the life of Nick Zappetti. It's honestly been 15 years since I read it, but I still remembered feeling that it was super difficult for a foreigner to become Japanese. It turns out I was wrong, and becoming legally Japanese is a straightforward process that can be undertaken by anyone.
I talked with Eido Inoue, a former American who became Japanese in 2010. Since naturalizing he's run a website (http://bit.ly/becojapan) educating people on how to naturalize and become a citizen of Japan.
The interview was so fascinating, that I have posted the mostly uncut hour-long version of the interview on the LWIF X channel at https://youtu.be/Yj855k5066o.
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