How did Japanese moves into China illustrate the radicalization of Japan’s empire?

After World War I, Japan’s modern, constitutional democracy began to crumble. Why? What factors caused Japan’s slide toward rule by the military in the 1930s? How did Japanese moves into China illustrate the radicalization of Japan’s empire? Please cite from the Goto-Jones reading. 
Please use internal citations from the sources you use in your response, and write at least 500 words. 
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