Mouwembleem US Japanese Logistic Command (Sleeve badge US Army japanese Log Cmd )

After the Japanese surrender in World War II, the United States Armed Forces assumed administrative authority in Japan. The Japanese Imperial Army and Navy were decommissioned, and the U.S. Armed Forces took control of their military bases until the new government could be formed and positioned to reestablish authority. Allied forces planned to demilitarize Japan, and new government adopted the Constitution of Japan with a no-armed-force clause in 1947.

After the Korean War began in 1950, Douglas MacArthur, the Supreme Commander of the Allied Powers in Japan and the Japanese government established the paramilitary "National Police Reserve," which was later developed into the Japan Self-Defense Forces.

In 1951 the Treaty of San Francisco was signed by the allied countries and Japan, which restored its formal sovereignty. At the same time, the U.S. and Japan signed the Japan-America Security Alliance. By this treaty, USFJ is responsible for the defense of Japan. As part of this agreement, the Japanese government requested that the U.S. military bases remain in Japan, and agreed to provide funds and various interests specified in the Status of Forces Agreement. At the expiration of the treaty, the United States and Japan signed the new Treaty of Mutual Cooperation and Security between the United States and Japan. The status of the United States Forces Japan was defined in the U.S.-Japan Status of Forces Agreement. This treaty is still in effect, and it forms the basis of Japan's foreign policy. According to academics and experts, the U.S. provision of Japan's defense allowed Japan to focus domestic spending on their own economy, thereby assisting Japan with becoming one of the most powerful countries economically in the world