What was a primary reason for the soviet union's and the united states' decision to engage in a cold war rather than a hot war?

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roosevelt essentially took the opposite approach as hoover in taking on the great depression. herbert hoover thought that america and its economy could naturally recover from the depression in due course, so he adamantly restrained the federal government from intervening on behalf of the people affected. on the other hand, roosevelt dramatically increased employment by expanding the federal government and establishing agencies that would aid in relieving some of the country's worst problems.

there are many answers to this question, such as a diplomat, ambassador, soldier, united nations employee, cia, etc.