The Vietnam War was one of the wars that was fought by allies of the US and USSR, and that had an impact on the relationships between the countries and the alliances created. Essentially, the Vietnam War started after the creation of the two Vietnam states, in which the North was under Communist rule, while the South was under the rule of Diem, an unpopular leader. North Vietnam, with help from China and Russia, was able to fight a guerrilla war, and essentially defeat the USA (which did not have any experience in the jungle warfare with their present generation), as well as usurp and reunite the country under Communist rule. The War was fought mostly in dense, jungle areas, with swamps, and predators, allowing for guerrilla warfare to be the the best fighting style. While the USA tried the best to fight, they were not ready for war, and the home front did not essentially support the war, though Nixon (the president of US during the time) believed that there was a 'silent majority' that supported the war. In the end, the US had to pull out their troops, and with no more military support, the South Vietnamese government surrendered to the North, making Vietnam a full Communist state.
While it was a defeat to the US and brought about changes in the US structure, the war showed the US that they were not invincible as they thought (starting from WWII), and that they had to rethink their doctrine of war.
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