Factors that supported militarism in Japan
 

The samurai legacy: Even though Edo period Japan enjoyed 250 years of peace, it was ruled by a warrior-bureaucrat elite, that held up bushido, the way of the warrior.
The Meiji Constitution: Set up in 1889, it granted the military right of direct access to the emperor, following the Prussian example.
Weakness of Party Government: The government of Taisho Japan faced mass protests, assassinations and coups d'etat and corruption.
Discontent of the Military: Military leaders were dissatisfied with Japan's achievements on the diplomatic field. There was a strong feeling of humiliation by Western powers.
Polarized Political Climate: Strong left-wing and right-wing groups battled each other and weakened the government.
Economic Depression: Japan suffered population explosion in the 1920s. Its newly globalized economy was hit by the Great Depression in 1929
Totalitarian examples in Europe: Fascism in Italy which rose in 1922, and Nazism in Germany which rose in 1933 set successful examples for the Japanese militarists.

Re: Factors that supported militarism in Japan
 

Note also that Japanese schools were militarized from the primary grades onward. While I was learning to read "Run Spot, run!" my contemporaries in Japan were learning to read the exploits of Japanese soldiers in China. Blue skies! -- Dan Ford