The Vietnam War, also known as the Second Indochina War (called the Vietnam War), was fought from 1964 (events in the Gulf of Tonkin) or from 1965 (the landing of the first, larger American forces in Vietnam) until 1975, i.e. until the occupation of South Vietnam through North Vietnam. The opponents in this war were, on the one hand, the United States, supporting its ally, i.e. South Vietnam and North Vietnam, along with the communist Vietcong guerrillas, supported (in one way or another) by the PRC and the USSR. Assume that at one time, at the maximum, North Vietnam involved about 690,000 soldiers in the conflict, Vietcong - about 200,000 people, while the United States reached the peak of its involvement in 1969, when Vietnam had about 540,000 American soldiers. The immediate cause of the conflict was the claims and ambitions of North Vietnam to take power and control over its southern neighbor, which the United States could not and did not want to agree to. The Vietnam War was an excellent example of a guerrilla war, in which the highly advanced technological armed forces of the USA suffered considerable losses and finally lost in the clash with the armed forces incomparably worse. It is worth adding that from a purely military point of view, the US troops were able to inflict huge losses on their opponent (e.g. the Tet offensive of 1968), but on the so-called The "home front" completely lost it. It is often assumed that the Vietnam War was lost by the US primarily because of tensions in American society, its reluctance to do so, and the inability of the US establishment to provide a convincing justification for it. The Vietnam War finally ended in 1975 with a complete defeat of the United States, which was forced to withdraw from Vietnam and come to terms with the unification of Vietnam by the communist government in Hanoi. The prestige of this country in the international arena has also decreased significantly for some time.