Japan’s GDP is 5th in the world, at about $4.5 trillion. Of which they currently spend about 1%, about $45 billion on defense each year.
With the US more than willing to provide Japan with the technology it needs to create nuclear weapons, including the very high grade nuclear fuel *and* the uniquely high quality nuclear klystron tubes that very precisely set off the explosives that thrust the nuclear matter together creating a much greater yield, yeah, Friday is about right.
That is, unless we have a few of our own we are willing to let Japan use. Which we probably are.
Comparatively, North Korea’s nuclear and missile technology is first going on second generation, and is even questionable if it can work. Which it might, but getting it to target through a gauntlet of more advanced anti-missile missiles, is well, say, problematic.
After 68 years, the Japanese probably have a lot of tension built up that they would be more than happy to take out on a belligerent pain in the rear end, like North Korea.
Many have suspected that Japan has had nuclear weapons for decades, as has Israel. All they have to do is have an excuse to bring them out of their caves...........