The Soviet Union's participation in the United Nations was primarily to reduce the power of the United States following World War II. This involvement allowed the USSR to promote its agenda and influence global governance. While preventing future wars was a potential objective, it was secondary to their strategic interests. ;
The Soviet Union participated in the United Nations primarily to reduce the power of the United States following World War II. This involvement allowed the USSR to influence global governance and assert its presence on the international stage. Therefore, option B is the correct choice.
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