I won't say that is impossible, but anyone wanting to execute on it needs to have a team where everyone speaks a lot better Japanese than I do, and your odds of recruiting that team stateside are pretty slim.
I was thinking more of a team of entrepreneurial native Japanese who simply decided to do it in US in search of better start-up culture.
Feel free to talk to Japanese entrepreneurs about their sorrows sometime, because I don't want to speak for them, but I don't think moving to the US addresses the concerns of the three stakeholders who I generally hear mentioned: girlfriends, parents, and prospective future employers.
Maybe some US funds could offer a good "cover story" for Japanese immigrants if they fail?