Answer:
At the end of the Second World War, the Allied side, which was formed mainly by the powers of the United States, the Soviet Union, Great Britain and France, divided itself in ideological terms into two distinct camps, led by the United States and the Soviet Union, respectively. Thus, the side led by the United States, called the Western bloc, advocated the imposition of a democratic and capitalist system throughout the planet with a fundamental respect for the individual freedoms of citizens, both in social and economic terms. On the other hand, the Soviet Union came to lead in the eastern bloc, with clearly communist ideas, which promoted the creation of an authoritarian system in which the government would centralize economic, political, civil and social decisions both at a general level as well as in the particular scope of each one of the citizens.
In this way, these two antagonistic views of the world began to collide, since both powers sought to expand their spheres of influence through the imposition of their system in other countries. This situation, motivated by the power struggle between both powers, gave rise to the Cold War.
They were first mentioned by the political philosopher John Locke. He was very influential for the founding fathers who based the ideas of rights that are self evident on his philosophy. According to him, the natural rights were those of life, liberty, and property, a bit different than what ended in the final documents.
