The US and Russia avoided conflict with each other before and after the atom bomb, and also before and after the UN made it illegal. I'm not sure either were essential or even effective deterrents.
In fairness, the US did come into conflict with Russia in a sense, by supporting the White Army in the civil war.
But setting that aside, when would they have come into conflict? Prior to WWI, the US did its best to stay out of international affairs, and Russia wasn't trying to export a political philosophy. In the gap between the wars, the Soviet Union was preoccupied with internal concerns.
It's very hard to compare the potential for conflict post-1945 between the two powers with any period of time before that. Russia and the US simply weren't all that relevant to each other (Alaska aside).
But setting that aside, when would they have come into conflict? Prior to WWI, the US did its best to stay out of international affairs, and Russia wasn't trying to export a political philosophy. In the gap between the wars, the Soviet Union was preoccupied with internal concerns.
It's very hard to compare the potential for conflict post-1945 between the two powers with any period of time before that. Russia and the US simply weren't all that relevant to each other (Alaska aside).