Kaikoku heidan

Hayashi Shihei's Kaikoku heidan (1787), meaning "A Discussion of the Military Problems of a Maritime Country," was a 16-volume work that highlighted Japan's inadequate military and maritime defenses. Hayashi, a scholar of military affairs, was concerned about the intentions of Western powers, particularly Russia's southward advance from Siberia. He advocated for stronger military forces and a robust maritime defense capability, criticizing Japan's "closed-door" policy and ignorance of the outside world. The work generated significant interest but was banned by the shogunate for discussing national defense matters without official sanction, leading to Hayashi's house arrest.1