Unified Socialist Party of Mexico - Wikipedia
The Unified Socialist Party of Mexico (Spanish: Partido Socialista Unificado de México, PSUM) was a socialist political party in Mexico.It later became the Socialist Mexican Party (Partido Mexicano Socialista) in 1988.. History. The PSUM was founded in November 1981 by the merger of four socialist parties: . The Mexican Communist Party (Partido Comunista Mexicano, PCM) - …