I'm interested in our learned friend's thoughts, but would offer my two cents. My understanding was that the Meiji Restoration through WWI was a time of fast modernization and industrialization where the Japanese sought to develop along European lines. The Army was modeled on European armies and behaved along those lines.
But extreme nationalist sentiments were building, beginning when after winning the Russo-Japanese War, European powers and American pressured Japan into giving back some of her gains. The 1920's were a turbulent time when civilian government was losing credibility to extreme nationalists, who had an increasingly racist view of non-Japanese. By 1930 an Army dominated by extreme nationalists was operating practically without any civilian governmental control.
There was also great resentment of America in Japan. Teddy Roosevelt had pressured them over the Russian peace. The Exclusion Act was greatly resented. The militarists were offended by the Washington Naval Treaty ratios. So, there were not very friendly feelings toward us to check the militarists attitude.
The bottom line is I agree with you that there was something virulent and malignant going on during the interwar years in Japan.
It's such a shame that Obama wasn't born eighty years earlier so he could have given them everything they wanted.