What if Mutsuhito (the Emperor Meiji) remained convinced of the desirability of Saigo Takamori's plan to invade Korea in 1873 and endorsed prompt action, instead of insisting on consultation with various ministers who were traveling abroad.
The Japanese invade Korea in 1873 with a bunch of Samurai and the limited amount of western tech they had at the time.
What happens?
Takamori and Mutsuhito's Excellent Adventure?
or
Takamori and Mutsuhito's terrible, horrible, very bad, no good day?