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The main countries involved in the Vietnam War were North and South Vietnam. South Vietnam was backed by anti-communist countries and members of the South East Asia Treaty Organization (SEATO) which included the United States, South Korea, Australia, the Philippines, New Zealand, Thailand, Khmer Republic, Kingdom of Laos and Republic of China (Taiwan). Most of these countries offered air support in form of trained pilots and some were technical advisers
North Vietnam was backed by the communist allies which included People’s Republic of China, Soviet Union, Pathet Lao (Laotian Communist insurgents), Khmer Rouge (Cambodian Communist insurgents) and North Korea. Notably People's Republic of China constructed the rails and infrastructure that were bomber ed during the war.
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