Although Japan had some labor unions in the early 20th century, they did not have the right to bargain collectively with employers and their legal status was weak. Then in 1940, the labor unions dissolved and their members joined the government-sponsored national workers' organization Sampo, as part of a wartime national reorganization of all civil organizations under central government direction. Sampo remained in existence at the end of the war. American Occupation authorities encouraged Japanese workers to form independent labor unions as early as fall, 1945. A new labor union law was passed in December and took effect in March 1946. The number of workers in unions rose very dramatically from about 5,000 in October 1945, to 5 million by February, 1947. The Occupation General Headquarters (GHQ) initially encouraged the formation of labor unions, but became alarmed when the Sanbetsu labor federation affiliated with the Japan Communist Party and the Sōdōmei labor federation affiliated with the Japan Socialist Party planned a nationwide, open-ended general strike for February 1, 1947. A nationwide general strike would mean that all communications, transportation, production facilities, and public services would shut down. The Occupation banned the general strike the day before it was supposed to begin, and this marked a turning point in Occupation support for labor.