Fierce rivalry between the Army and Navy in Imperial Japan was a major handicap to Japan’s war effort. How did two branches of the same national military end up so bitterly hostile to each other?

by Tough_Guys_Wear_Pink

Legitimate_Twist

While more can obviously said, you can refer to these answers in the meantime:

/u/kieslowskifan's answer here.

/u/Bacarruda's answer here.