After Japan's defeat in
World War II and the collapse of the militarist regime, Takano returned to labor activism under the
U.S. Occupation, which legalized labor unions and explicitly protected labor organizing in the new Japanese Constitution promulgated at the Occupation's behest in 1947. In 1950 Takano played a central role in the creation of the
General Council of Trade Unions of Japan (better known by its Japanese abbreviation
Sōhyō), and in 1951, he was elected its first secretary-general. Sōhyō had been formed with the connivance of Occupation authorities, as what they hoped would be a moderate, centrist alternative to the militant, JCP-affiliated labor unions that had dominated the Japanese labor movement prior to the
Red Purge of 1948–1950. However, Takano was no moderate, and he immediately set about instilling in the new organization his vision of wide-ranging social activism extending far beyond workplace issues to encompass a broad array of left-wing social and political causes, becoming the leading figure in Sōhyō's dramatic "left turn." With the JCP in disarray following the Red Purge and a disastrous flirtation with armed revolution, Takano led Sōhyō into the embrace of the
Japan Socialist Party (JSP) instead. As secretary-general, Takano played a leading role in organizing protests by Sōhyō-affiliated labor unionists against the Anti-Subversive Activities Law of 1952, and against the U.S. artillery range in the Uchinada sand dunes from 1952 to 1953, as well as against the U.S. nuclear testing in the wake of the
Lucky Dragon nuclear fallout incident of 1954. He also presided over a series of increasingly militant workplace struggles and strikes, thereby instilling both political and labor militancy in Sōhyō's organizational DNA. However, in 1953, Takano crossed a bridge too far when he introduced his "Peace Force Thesis," whereby Takano sought to align Sōhyō with the "peaceful" Soviet Union and Communist China against the "warlike" United States. This stance provoked a chorus of criticism from within both Sōhyō and the JSP. The following year, three of Sōhyō's largest unions bolted to form the more moderate, openly anti-communist
Zenrō labor federation, precipitating the ouster of Takano. In 1955,
Akira Iwai was elected Sōhyō's new secretary-general, with a mandate to pursue a more moderate policy line. ==Later life==