Earlier quoted context omitted.
> Japan can change this on a whim with one meeting of the legislature. They literally cannot. > You think Japan can't change its own laws? It can't amend the Constitution just with a vote in the Diet; it requires a supermajority in both Houses followed by a popular referendum.
Laws are just words on paper. They are irrelevant without people to follow and enforce them. It is very common for Constitutional laws to be suspended in the event of war. Even without suspension, all it takes is a leader with enough support to ignore the law.
Which is to say, no: No Japanese leader has had the kind of support necessary to ignore the law.