Japan is a great power and a member of numerous international organizations, including the United Nations (since 1956), the OECD, and the Group of Seven. Although it has renounced its right to declare war, the country maintains Self-Defense Forces that rank as one of the world's strongest militaries. After World War II, Japan experienced record growth in an economic miracle, becoming the second-largest economy in the world by 1990. As of 2021, the country's economy is the third-largest by nominal GDP and the fourth-largest by PPP. Japan has close economic and military relations with the United States, with which it maintains a security alliance. The United States is a major market for Japanese exports and a major source of Japanese imports, and is committed to defending the country, with military bases in Japan. Japan's relationship with South Korea had historically been strained because of Japan's treatment of Koreans during Japanese colonial rule, particularly over the issue of Japan's military using Korean comfort women in World War II. In 2015, Japan agreed to settle the comfort women dispute with South Korea by issuing a formal apology and paying money to the surviving comfort women. Japan is engaged in several territorial disputes with North Korea, South Korea, Russia, China and Taiwan. Relations with Russia have been strained due to Japan's rejection of Russian control of the Southern Kuril Islands, since 1945. For current issues see Foreign relations of Japan. Policy making by Prime Minister The primary responsibility for the Japanese foreign policy, as determined by the 1947 constitution, is exercised by the cabinet and subject to the overall supervision of the National Diet. The prime minister is required to make periodic reports on foreign relations to the Diet, whose upper and lower houses each have a foreign affairs committee. Each committee reports on its deliberations to plenary sessions of the chamber to which it belongs. Special committees are formed occasionally to consider special . Diet members have the right to raise pertinent policy questions—officially termed interpellations—to the minister of foreign affairs and the prime minister. Treaties with foreign countries require ratification by the Diet. As head of state, the emperor performs the ceremonial function of receiving foreign envoys and attesting to foreign treaties ratified by the Diet. Before 1945 the Emperor had a major voice in setting policy. Constitutionally since 1945 the dominant figure in the political system, the prime minister has