and official Marxism in China were reworked. This new model was a newer dynamic form of Marxism–Leninism and Maoism in China. Commonly referred to as socialism with Chinese Characteristics, this new path was centred around Deng's Four Cardinal Principles, which sought to uphold the central role of the Chinese Communist Party and uphold the principle that China was in the primary stage of socialism and that it was still working to build a communist society based on Marxist principles. Late 20th century In 1959, the Cuban Revolution led to the victory of Fidel Castro and his July 26 Movement. Although the revolution was not explicitly socialist, upon victory, Castro ascended to the position of prime minister and adopted the Leninist model of socialist development, allying with the Soviet Union. One of the leaders of the revolution, the Argentine Marxist revolutionary Che Guevara, subsequently went on to aid revolutionary socialist movements in Congo-Kinshasa and Bolivia, eventually being killed by the Bolivian government, possibly on the orders of the Central Intelligence Agency (CIA), although the CIA agent sent to search for Guevara, Felix Rodriguez, expressed a desire to keep him alive as a possible bargaining tool with the Cuban government. He posthumously went on to become an internationally recognised icon. In the People's Republic of China, the Maoist government undertook the Cultural Revolution from 1966 to 1976 to purge Chinese society of capitalist elements and achieve socialism. Upon Mao Zedong's death, his rivals seized political power, and under the leadership of Deng Xiaoping, many of Mao's Cultural Revolution era policies were revised or abandoned, and much of the state sector was privatised. The late 1980s and early 1990s saw the collapse of most of those socialist states that had professed a Marxist–Leninist ideology. In the late 1970s and early 1980s, the emergence of the New Right and neoliberal capitalism as the dominant ideological trends in Western politics championed by United States president Ronald Reagan and British prime minister Margaret Thatcher led the West to take a more aggressive stance towards the Soviet Union and its Leninist allies. Meanwhile, the reformist Mikhael Gorbachev became General Secretary of the Communist Party of the Soviet Union in March 1985 and sought to abandon Leninist development models toward social democracy. Ultimately, Gorbachev's reforms, coupled with rising levels of popular ethnic nationalism, led to the dissolution of the Soviet Union in late 1991 into a series of