I think that's a very unhelpful way of putting the matter.
There is no direct confrontation standing at the origin of the conflict. Hence it being a 'Cold' War. It emerged from an accumulation of strategic moves over time. Each power worked to advance its interests, while watching other powers (namely Germany, Japan, and the British Empire) fade. At some point, they recognised that they were in direct geopolitical competition. When they did, it was clear that the Soviet Union was the lesser power. Its actions reflected that reality.
If you did want to identify an 'originary' moment to the conflict - which again, I think is an unhelpful way of approaching the subject - then it would have to be the US intervention in the Russian Civil War against the Bolsheviks.
There is no direct confrontation standing at the origin of the conflict. Hence it being a 'Cold' War. It emerged from an accumulation of strategic moves over time. Each power worked to advance its interests, while watching other powers (namely Germany, Japan, and the British Empire) fade. At some point, they recognised that they were in direct geopolitical competition. When they did, it was clear that the Soviet Union was the lesser power. Its actions reflected that reality.
If you did want to identify an 'originary' moment to the conflict - which again, I think is an unhelpful way of approaching the subject - then it would have to be the US intervention in the Russian Civil War against the Bolsheviks.