Seikanron

The Seikanron (Japanese: 征韓論; Korean: 정한론; literally "Advocacy of a punitive expedition to Korea") debate was a major political debate in Japan in 1873 regarding the immediate invasion of Korea. It was decided that no action was to be taken against Korea.

After the Meiji Restoration and the overthrow of the Shogunate in 1868, the newly formed Meiji government embarked on reforms to centralize and modernize Japan. The Imperial side did not pursue its objective to expel foreign interests from Japan instead adhering to the treaties signed during the bakumatsu period with the ultimate goal of revising them and building up the nation's strength by continuing with reforms begun under the shogunate. In foreign affairs, the government had taken steps to establish a foreign affairs bureau to take over Japan's external relations which was previously conducted by the bakufu.

Although the shogunate had been overthrown, the Ōuetsu Reppan Dōmei an alliance of northeastern domains continued resistance to the new government. Enomoto Takeaki a former shogunate naval officer had taken control of the eight of the best warships of the Shogun's navy and joined the northeastern alliance. After the defeat of the Ōuetsu Reppan Dōmei, he had fled farther north to Hokkaido where he occupied the city of Hakodate and set up the Republic of Ezo. In the spring of 1869, the central government began operations against the last stronghold of military opposition and in May 1869 opposition forces surrendered. Enomoto Takeakis' refusal to surrender and his escape to Hokkaidō with a large part of former Tokugawa Navy's best warships embarrassed the Meiji government politically. The imperial side had to rely on considerable military assistance from the most powerful domains as the government did not have enough power, especially naval power, to defeat Enomoto on its own. Although the rebel forces in Hokkaidō surrendered, the government's response to the rebellion demonstrated the need for a strong centralized government. Even before the incident the restoration leaders had realized the need for greater political, economic and military centralization

Serious divisions emerged in the restoration coalition that had overthrown the Shogunate. Reforms enacted by the Meiji government such as the abolition of the domains led to resentment.

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