It has long been accepted, almost as a Cold War truism, that the first direct confrontation between Soviet Russia and the United States took place over Iran in February, 1946. According to the traditional picture of Cold War origins, Russia's refusal to evacuate her forces--together with her simultaneous efforts to establish a puppet regime in Azerbaijan and Kurdistan--tipped the West off as to her global intentions. America and Great Britain promptly registered protests within and outside the United Nations, and, in the first effort at containment, prevented direct Soviet penetration of the entire Middle East. After Iran, the West was forewarned. As a leading textbook notes, in pointing to Russia's reluctance to withdraw, “Soviet power was prepared to move into any position that the Western states were not willing to defend.”
Most memoirs of American policy-makers stress that the United States had responded, and responded of necessity, to Russian incentive.