During the war, the policies that would govern the occupation of Japan had been the subject of sharp debate in Washington. Although some advocated doing away with the influence of prewar Japanese moderates altogether, in the end a great deal was left to the initiative of the supreme commander. The Potsdam Declaration had pledged that postwar Japan would guarantee freedom of speech, religion, and thought and respect fundamental human rights. The Japanese government was to remove all obstacles to the revival and strengthening of democratic tendencies among the Japanese people.

On August 29, 1945, a document outlining the initial U.S. post-surrender policy for Japan was worked out by the Departments of State, War, and the Navy; this became the basic statement of principles. As its ultimate objective, it envisaged Japan as no longer a threat to the peace and security of the world, ruled by a responsible government which would respect the rights of other states and support the objectives of the charter of the United Nations. The U.S. did not wish to impose any form of rule that ran contrary to the freely expressed will of the Japanese people, but it was hoped that Japan would conform as closely as possible to principles of democratic self-government. Japan would be limited to the four main islands and such minor islands as were to be specified at a later date. The Soviets had laid claim to the Kuril Islands as a condition of their declaration of war; that transfer was formalized in 1951, and the entire Japanese population of the archipelago was forcibly repatriated. Japan was to be disarmed and demilitarized, with the influence of the militarists “totally eliminated” from political, economic, and social life. The Japanese people would be encouraged to develop a respect for individual liberties and human rights, and they would be given the opportunity to develop an economy adequate to meet the peacetime requirements of the population.

Power to carry out these objectives was given to Gen. Douglas MacArthur, Supreme Commander for the Allied Powers (SCAP). By agreement of the U.S., British, and Soviet foreign ministers, a Far Eastern Commission representing all the Pacific allies was established for the formulation of policies and review of MacArthur’s actions, but whatever recommendations and directives ensued would reach him through normal military channels. An Allied council for Japan, representing the Soviet Union, China, the British Commonwealth, and the supreme commander, sat in Tokyo to furnish on-the-spot advice and consultation. The supreme commander was to consult this council before issuing orders, the exigencies of the situation permitting, but the final decision was his. In practice, SCAP paid the Allied council little heed and acted swiftly to forestall Far Eastern Commission directives. As a result, he was little hampered by outside interference, and the occupation was thus largely a U.S. affair. SCAP became a large organization of several thousand persons, including both the headquarters staff of the Pacific campaigns and personnel who provided the technical, administrative, and bureaucratic staffs. MacArthur worked through the Japanese government and made his wishes known by directives or more discreet suggestions. He had to be consulted on all major decisions of policy or politics and thus functioned somewhat in the manner of the genro of an earlier day.

The efforts at democratizing Japanese society seemed successively radical and cautious, and they were criticized as doctrinaire and half-hearted by turn. The spirit of reform gave way to an emphasis on rebuilding and resuming production, as external factors sparked concern about excessive social and political change. It is evident that the victory of the Communists in the Chinese Civil War altered the U.S. view of Japan’s role in international affairs and increased the desirability of speeding Japan’s economic recovery. The SCAP attitude toward communism, labour, and deconcentration underwent decided changes. However, historians largely agreed that the measures taken by SCAP created an open political environment in which new forces could and did rise. Such trends proved successful and lasting in areas where occupation measures had coincided with trends toward change long present, though suppressed, within Japanese society.

The early months of the occupation saw SCAP move swiftly to remove the principal supports of the militarist state under which Japan had gone to war. The armed forces were demobilized, State Shintō was disestablished, and nationalist organizations were abolished and their members barred from holding important posts. Other purges removed from active roles all individuals prominent in wartime organizations and politics, including commissioned officers of the armed services; this was later extended to include all high executives of the principal industrial firms. In Tokyo the International Military Tribunal for the Far East tried Tōjō and other leaders for war crimes, sentencing 7 to death, 16 to life imprisonment, and 2 to shorter terms. Millions of Japanese were repatriated from the former colonies and from Southeast Asia.

The Home Ministry, which had controlled wartime Japan through its appointive governors and national police, was abolished, and the Education Ministry was deprived of its sweeping powers to control compulsory education. Since central control and military influence were being dismantled by a military government which needed centralized powers in order to be effective, the occupation’s role was often a contradictory one. In the course of issuing instructions to the Japanese government to make certain that changes were being carried out, SCAP ensured the survival of that government as one intimately concerned with the pattern of local events in all parts of the country. In many cases, factors of geography and economic rationality reinforced the logic of centralization, and some of the moves toward decentralization were soon modified or reversed.

Political reform and the 1947 “peace” constitution

The new political structure of Japan centred on a new democratic constitution. The indirect rule, unseen cliques, and shadowy nature of the real power behind the facade of imperial rule made the Meiji Constitution clearly inadequate, and SCAP informed Japanese leaders that constitutional reform should receive first attention. The veterans of earlier decades of parliamentary government proved unable to grasp or accept the kind of reform that was intended. Between October 1945 and February 1946 a cabinet committee headed by Matsumoto Jōji prepared revisions to the Meiji Constitution. However, when the resulting draft was submitted to SCAP, it proved to contain few and superficial changes. MacArthur’s government section rushed a new draft to completion in six days. This document was then submitted to the Japanese government as the basis for further Japanese deliberations. Despite the misgivings of conservative statesmen, it was approved by the emperor and submitted for amendment to the first postwar Diet, which had been elected in April 1946—the first Japanese elections in which women voted. The constitution, slightly modified, went into effect on May 3, 1947.

Its preface stated in ringing tones the intention of the Japanese people to ensure peaceful cooperation with all nations and the blessings of liberty for themselves and their descendants. The constitution included a 31-article bill of rights. Perhaps most notable of these was Article 9, which renounced war as a “sovereign right of the nation” and pledged that “land, sea, and air forces, as well as other war potential, will never be maintained.” The emperor, who had renounced his claim to divinity on January 1, 1946, was described as the “symbol of the state and of the unity of the people, deriving his position from the will of the people with whom resides sovereign power.” The prewar Meiji Constitution had described him as “sacred and inviolable.” The constitution provided for a bicameral Diet, with the greatest power vested in a House of Representatives whose members served for four-year terms. The old peerage was dissolved, and the House of Peers was replaced by a House of Councilors whose members served six-year terms. The prime minister was to be chosen by the Diet from among its members, and an independent judiciary, as in the U.S., had the right of judicial review.

The new constitution thus reversed the Meiji pattern that had placed all sovereignty in the imperial institution, from which power could be drawn by imperial household officials, military officers, and the privy council as well as by the prime minister. With the removal of the military service heads, the privy council, and the peers and with a clearly nonpolitical role specified for the emperor, authority lay solely with the elected Diet, which selected the executive from its ranks. For the first time in modern Japan, the nature and role of the executive were clearly defined. Parallel changes made prefectural governors and other local officials elective so that the government could be responsive to the popular will.

The 1947 constitution was drawn up hastily, and subsequent research by Japanese scholars led to the suspicion that SCAP had rushed to head off the recommendations of the Far Eastern Commission. Despite this, the constitution worked well, and it gained widespread support in Japan. Because its implementation coincided with the purge of most of the leaders of prewar and wartime Japan, conditions were favourable for the development of new ideas and methods.

By the time the Treaty of Peace with Japan went into effect in 1952, elements of the political pattern had already changed, and subsequent governments showed their ability to modify by administrative actions a constitution that remained unchanged. Decentralization in some fields had proven expensive and inefficient. The police, for instance, while less centralized than in Home Ministry days, had returned to a substantially national organization. Despite the announced goals of local decentralization, changing patterns of communications and administration had shown the logic of incorporating many small units of administration into larger units, a trend particularly marked in the countryside where villages and towns merged to form a more rational tax structure. Article 9 of the constitution was compromised by the decision taken by SCAP to form a “police reserve” of 75,000 men during the Korean War. This body, renamed the Self-Defense Force in 1954, came to number roughly 250,000 in the 21st century.

Nevertheless, the basic principles of the 1947 constitution enjoyed support among all factions in Japanese politics. Executive leadership was a chief asset of the new institutions. With the abolition of competing forces that had beset the premiers of the 1930s, the postwar prime ministers found themselves in charge of the administration and, with rearmament, the armed forces as well. Thus, responsible leadership gradually replaced the ambiguous claims of imperial rule of earlier days.