I'm looking for a deeper answer than "strong political institutions" or "a disciplined society." What structural factors contributed to Japan having those institutions, and what structural factors discouraged them in China?
There are some previous questions on this or similar subjects (collated here) that you might find useful.
Adding to /u/tiredstars link (not sure if any overlap) - there's a decent section in the FAQ (which more people should check too) here.