The Treaty of San Francisco, signed on November 8, 1951, and implemented on April 28, 1952, restored full sovereignty to Japan after its unconditional surrender at the end of World War II and ended the U.S. occupation.
The negotiations over the treaty revealed differing notions of what had caused World War II and of what Japan’s role in the world should be. Engineered primarily by the United States, the treaty quickly became caught up in the cold war rivalries.
In March 1947 U.S. general Douglas MacArthur, who headed the Allied Occupation Authority in Japan, ignited a heated debate about the proper terms of Japan’s rehabilitation when he publicly stated his preference for a relatively short U.S. occupation, believing that Japan had been democratized and demilitarized and that a long occupation would only create resentment.
This view was countered by those who pushed for massive reparations from Japan as well as its complete demilitarization. This group believed that the lax enforcement of the Versailles Treaty, which had ended World War I and established terms for the German reparations and demilitarization, had created the conditions for World War II.
A different assessment of the Versailles Treaty emerged among those who advocated a "soft" approach to the peace treaty. This group, which eventually included U.S. secretary of state Dean Acheson as well as MacArthur, argued that it was the harsh conditions of Versailles that had, by humiliating and isolating Germany, contributed to the rise of Nazism. This group also worried that the United States should be careful not to overextend its military presence in Japan.
The negotiations were complicated by cold war diplomacy. The United States worried about granting Soviet Russia and the newly established communist People’s Republic of China a significant role.
It also wanted to guarantee that Japan would become a U.S.- friendly bulwark against communism in East Asia. In particular, the U.S. military wanted to retain control over Japan for an extended period to guarantee access to its military bases in the area.
The United States eventually adopted a "piecemeal strategy" of granting Japan full sovereignty and disregarding the calls for a longer occupation. It met the concerns of the British Commonwealth of Nations with a U.S.-backed security network that would include Australia and New Zealand.
It satisfied the concerns of the Philippines with promises of aid and security. The United States also decided that neither the Chinese Communist nor the Chinese Nationalist governments would be invited to the treaty conference. This formula won significant bipartisan support in the United States.
The official treaty conference took place in San Francisco in 1951. Fifty-one nations were represented (India chose not to attend). The United States engineered the simpulan result, causing delegates from the Soviet Union, Poland, and Czechoslovakia to walk out. Eventually 48 nations signed the treaty.
The simpulan terms of the treaty reflected a victory for the pragmatists who had worried that overly harsh conditions would push Japan away from the West. Although it stripped Japan of all territory gained since 1895 and rejected the pardoning of war criminals, the treaty established immediate sovereignty for Japan and limited reparations it owed to its World War II victim nations. The United States–Japan Security Treaty, signed two hours after the peace treaty, guaranteed a U.S. military presence.
Not all Japanese were happy with the treaty. Many Japanese wanted to see the process of democratization and demilitarization continued. They were surprised by the number of bases the United States maintained in Japan as well as the ban on diplomatic relations and trade with communist China.
In retrospect, the relatively generous terms of the treaty reformed Japan as an important member of the Western camp during the cold war. Japan never again threatened the security interests of the West or of other East Asian nations.