Which of these was a feature of the relationship between the soviet union and the united states in the era leading up to détente? nuclear war direct conflict arms race cooperation

The correct answer is - arms race.

The Soviet Union and the United States were competing on every field possible in order to show that they are superior, and the biggest power in the world. This was mostly demonstrated with the advancements in technology and weaponry. Both of the countries were producing new edge technology weapons, and they were making them more and more dangerous and devastating. It was an arms race to the maximum. This lead to the detente, where both countries agreed that they will ease up on the weapon production, and that they will limit their nuclear arsenal. Unfortunately, this was only how things were agreed on paper, while behind close doors, both countries continued with mass production of weapons for mass destruction.

each played a major role in ending the cold war.

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