While the United States had ample experience in the first half of the twentieth century, chasing Augusto Sandino up and down the mountains of Nicaragua or battling Aguinaldo’s forces in the Philippines, it was the Cold War that gave the United States its deepest experience – directly and indirectly – in dirty wars. As early as 1951, Washington was beginning to conclude that communist-led guerrilla insurgencies threatened American interests. According to a draft of a high-level classified government report, “communist-controlled guerrilla warfare represents one of the most potent instrumentalities in the arsenal of communist aggression on a worldwide basis.” According to this emerging estimation, the United States needed to take “practicable steps . . . to counter such guerrilla warfare.”

This growing recognition of the need to counter guerrilla subversion contrasted significantly with the preponderant doctrine at the time, which preached “massive retaliation” as the most effective deterrent against what was assumed to be an unyielding Soviet empire. Yet, while nuclear deterrence remained a pillar of American strategy, episodes such as the Suez Crisis in Egypt in 1956 led American policymakers to conclude that the Soviets were not just building long-range ballistic weapons but also were clandestinely arming and allying with anti-Western forces across the globe. Over the next several decades, the American public would become familiar with a number of places and events such as the Bay of Pigs and Vietnam that reinforced the idea that U.S. efforts to check Soviet-backed subversion now meant getting down in the weeds of counterinsurgency operations in faraway and previously unimportant locales.