The rise of Japanese militarism in the 1930s was due to a number of reasons.
First, Japan's traditional and cultural policy favoured the rise of militarism. Military tradition of samurai made it easy for the Japanese to accept militarists as leaders. Bushido which promoted martial spirit and good qualities of samurai made the Japanese believe that militarists were more reliable than the corrupt party politicians. The Japanese inclination of unquestioned obedience to authority also favoured the authoritarian rule of militarists. Legacies of the Meiji era such as Shintoism which stressed the divine origin of Tenno whom the militarists made a supporter of militarism, education reform which indoctrinated the Japanese with absolute loyalty and conscription which indoctrinated the Japanese with Bushido helped the rise of militarism.
Second, the rise of militarism was due to the weaknesses of the party government. The party government was politically weak. Political weaknesses like political struggles among the party politicians, collusion between party politicians and zaibatsu, and inability of the party government in solving the problems brought about by the Great Depression led to social discontent. The conciliatory foreign policy adopted by the party government as seen in the Washington Conference during which Japan was to disarm in favour of the US and Britain, abolition of the Anglo-Japanese Alliance etc. further weakened the party government. The effectiveness of totalitarian Italy and Germany in dealing with the Great Depression made it clear that the Japanese should rely on a strong military government.
The party government failed to solve social problems, leading to the rise of militarism. The discontented peasants and workers turned to support the militarists when they found the party government unable to solve the problem of exploitation but colluded with zaibatsu...