United Secretariat of the Fourth International

The Fourth International (FI), founded in 1938, is a Trotskyist international. In 1963, following a ten-year schism, the majorities of the two public factions of the Fourth International, the International Secretariat and the International Committee, reunited, electing a United Secretariat of the Fourth International. In 2003, the United Secretariat was replaced by an Executive Bureau and an International Committee, although some other Trotskyists still refer to the organisation as the USFI or USec.

The ISFI was the leadership body of the Fourth International, established in 1938. In 1953 many prominent members of the International, and supported by the majority of the Austrian, British, Chinese, French, New Zealand and Swiss sections together with the U.S. Socialist Workers Party organized against the views of Michel Pablo, a central leader of the ISFI who successfully argued for the FI to adapt to the growth of the social democratic and communist parties. This led to disagreements between supporters of the ISFI and those parties on how to build revolutionary parties. These tensions developed into a split, leading to the suspension of those parties which had formed the International Committee of the Fourth International (ICFI) late in November 1953.

Over the following ten years a majority of the two sides developed similar approaches to a number of major international problems: opposing Stalinism during the 1956 crises in Poland and Hungary, and supporting the Algerian War of Independence and the 1959 Cuban Revolution. At the same time, parties in the ISFI had retreated from Pablo's orientation to the communist parties. In 1960, the sections of the ICFI and ISFI reunited in Chile, India and Japan. In 1962, the political convergence between the majorities on both sides was strong enough for the ISFI and ICFI to establish a Parity Commission to prepare a joint World Congress. That congress aimed to reunify the Fourth International.

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