There was significant opposition to the militarists throughout the late stages of the Taisho era and Showa eras. This ranged from pro-western businessmen and thinkers, socialists, communists, and social democrats, outright fascists, more conservative military thinkers, and so on. However, a series of events caused a massive crackdown on dissent and simultaneously led to the rise of a government that was essentially controlled by the military.

Since the Meiji Restoration, Japan had a series of so-called Peace Preservation Laws that gradually made dissent more and more illegal, the process of which was accelerated by the Russian Revolution and the triumph of the Communists. In 1928, a major crackdown on socialists and other dissenters took place, where many such persons were arrested and forced to recant their beliefs. This essentially drove the socialists and communists underground.

On the pro-western side, partly due to the result of World War I and the Washington Naval Treaties, many Japanese officers were upset with the West and how they had treated Japan. They came into conflict with pro-western businessmen, including the heads of the zaibatsu that dominated Japan's economical output. Several of these zaibatsu heads, as well as domestic politicians, were murdered in a wave of assassinations committed by these hothead officers. This culminated in the 1932 assassination of Prime Minister Inukai, whereupon it became evident that to oppose the militarists was to invite death: indeed, Admiral Isoroku Yamamoto was considered for the position of Navy Minister but the idea was rejected in fear that the stubborn Yamamoto would antagonize the militarists, leading to his assassination.

Another important event to consider is the 2-26 incident, where a group of military officers launched a coup of the imperial government, hoping to bring about a "Showa Restoration" under military rule. While it failed, both the Emperor Showa and the government were both incensed and frightened, and ended up handing more power to the conservative faction of the militarists to head off the radical one. This led to increased suppression of foreign ideas (for instance, American jazz was banned, until Japanese jazz musicians convinced the authorities that Japanese jazz was different) as well as the introduction of what amounted to mass brainwashing. The Tokko special police acted as a sort of Stasi in controlling political dissent.

While there was still a certain amount of dissent, most notably in the announcement to attack Pearl Harbor (where many in the army navy opposed as it would result in war with the US, which they wanted to avoid at all costs) the strict disciplinary nature of the military combined with the autocratic control of the civilian populace resulted in a situation where Japanese resistance to the decisions that led to the war was very limited.