"While it is the substance, itself, that is banned, the purpose of its prohibition is to prevent people from partaking in its use. The authority says 'the way that those substances make you think is dangerous and we cannot allow you to think like that.'"

That's definitely what has been occurring in Japan. This country did not have much of a cannabis tradition since Meiji (possibly it did in earlier times - there's the use of cannabis seeds in several cooking spices; there was the prevalent use of hemp for fabric and rope making). For centuries, Japan has been an agricultural culture with a deep alcohol tradition. Since at least Tokugawa Era (early 1603 to 1868) there has been a heavy emphasis on restricting free will, etc. It appeared that keeping people drunk was an effective way to dull their thinking. By Meiji it was so firmly entrenched and went into hyper-drive with the push of the Nation State and intense competition with the non-Japanese. By 1946 when McArthur banned the use of cannabis, the Japanese government was more than happy to comply (since the society had eradicated its use in the culture by that time anyway except in the minor uses mentioned previously).

As a result, the mindset that is enhanced by the use of cannabis, hardly exists in this country. The vast majority is unaware and so is happy with the status quo. Unless a real education campaign is conducted here to spread such awareness, Japan will continue to have some of the world's harshest drug laws long after the U.S. decriminalizes cannabis; even though, the U.S. was the country that forced Japan to officially criminalize it in the first place. Without the perception or mindset that cannabis helps to expand, most Japanese will be stuck buried in the propaganda propagated during the height of the cannabis prohibition. Truly a sad state of affairs and damaging to anyone who wants the freedom to partake. Ignorance is bliss is far from the truth.