Responses will come in bits and pieces starting with this.

https://www.cia.gov/library/publicat...istory-CIA.pdf

The US Government had to learn how to conduct secret operations in the Cold War. Few precedents existed. The primary mission was relatively straightforward: predict if/how/when the Cold War could become a hot war—to prevent another Pearl Harbor. Paramilitary initiatives also followed from World War II experience.

But what about political warfare, that is, influencing political outcomes without
showing the hand of the US Government? The threat was relatively easy to
grasp, but the possible American responses took some time to develop. As the
eminent diplomat George Kennan put it, “We were alarmed at the inroads of…
Russian influence in Western Europe…particularly over the situation in France
and Italy. We felt that the communists were using…very extensive funds…to gain control of key elements of [political] life in France and Italy, particularly the…press, the labor unions, [and] student organizations.” To counter the threat, in 1948 the Truman Administration decided to use the CIA to provide secret campaign funds to Italy’s pro-western Christian Democratic Party. The Christian Democrats won the election, averting a possible communist takeover and establishing a precedent. The CIA proceeded with operations in Iran—in concert with the British—and in Guatemala to install pro-Western governments.