Its basic regional history, not my "say so." Japan had an extreme isolationist policy for the two hundred years leading up until the Meiji Restoration. https:/

Its basic regional history, not my "say so." Japan had an extreme isolationist policy for the two hundred years leading up until the Meiji Restoration. https://en.wikipedia.org/wiki/Sakoku https://en.wikipedia.org/wiki/Sakoku The Qing dynasty was on its last legs, following the disruption of the Opium wars, the chaos of the Taiping and Boxer rebellions, and the nascent, internal modernization movements. The independence of Korea's Joeson dynasty was put to an end when Yi Un was put under Japanese control by Ito Hirobumi in 1907. Taiwan quickly transitioned from being a Chinese Vassal state to a Japanese one. The Philippines had been colonized by the Spanish for a few hundred years, then the Americans in the period leading up to the war. They were able to so quickly build an empire because the countries around them were in a poor position to resist their sudden outburst of aggression.