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.The Vietnam War (1964 / 1965-1975) is a conflict fought between the government of South Vietnam, supported very intensively (economically, politically, militarily) by the United States, and North Vietnam, supported by the USSR and the PRC. On the American side, due to the very difficult terrain in Vietnam (jungle, numerous watercourses and canals, hills), the huge role of military mobility, especially their aeromobility, was quickly realized. Thanks to the latter, infantry units could move at a speed and pace impossible to achieve on land. This reflection, combined with the tests of a new type of troops carried out from the beginning of the 1960s, led to the creation in 1965 of the aeromobile division - the 1st Cavalry (Air) Division.[ang. 1st Cavalry Division (Airmobile)] . At the time of its formation, it consisted of three airmobile infantry brigades, each of which consisted of three infantry battalions. In addition, the division also included an artillery brigade in the strength of four battalions of 105 mm caliber howitzers and air rocket artillery. In addition, there were support units. The division underwent its baptism of fire in 1965 during the Battle of la Drang. It is worth adding that the 1st Cavalry Division (Airmobile) is considered to be the unit that suffered the greatest losses in the wounded and killed during the Vietnam War. It is also worth adding that in 1970, the 9th Air Cavalry Brigade was formed from the forces of the 1st Cavalry Division (Airmobile), which, despite its high efficiency, was disbanded just a year later.