Korea was located opposite of Japan. Its coal and iron resources made Korea attractive to Japan. They didn’t care how long Korea had been doing business with China, they still pursued them (Sino-Japanese War). Unlike China, Japan had westernized since the Industrial Revolution and had become a great power that was capable of defending itself against other countries (Sino-Japanese War, 1894–1895). While Japan had modernized quickly, China still considered Korea to be a vassal state (Dobbs).