Besides, right now
Sure, some people will claim that. But just because Japan has the capability, does NOT mean that Japan will want to pursuit that route. In fact, I would think that I can see the plausibility or even the desire for Japan to have actually pursued that route 30-40 years ago, in 1980s and 1990s. Today, however, I don't see it at all.
you have totally deflected the question, the question is not about japs' will.