The “Fat Man“-type plutonium bombs produced during the Manhattan Project used explosive compression of plutonium to obtain significantly higher densities than normal, combined with a central neutron source to begin the reaction and increase efficiency. Thus only 6.2 kg of plutonium was needed for an explosive yield equivalent to 20 kilotons of TNT.[64][74] (See also Nuclear weapon design.) Hypothetically, as little as 4 kg of plutonium—and maybe even less—could be used to make a single atomic bomb using very sophisticated assembly designs.–Wikipedia

I’ll assume we’re talking metric tons here.

Japan isn’t quite as pretentious as the Usurious Soviets of Amerika but it competes in the same suicidal hypocrisy big league.   There are 1000 kg in a metric ton so we’re talking an officially disclosed 30,000 kg of plutonium, meaning that nature loving, peace-seeking, eternally victimized Japan has the potential of making 7500 nukes.

But I bet Yoichi Shimatsu is right.  Japan already has a secret nuclear weapons program and that is why it is obsessed with fissioning McArthur River and Olympic Dam uranium atoms.   There ain’t no fun in traditional alchemy. Glenn Seaborg has brought his plutonian bitch, Atomic Anne, to this party and suicide cocktails are the rage.

エコ my ass, Japan.  You pretend Volcano Fukushima is nothing because don’t want the masses eating you for lunch and you also hide an image-destroying explosive mess.

And, oh yeah, Israel HAARPED Japan for being an international good guy.