Answer:
During the Cold War the United States advocated liberal democracy while the Soviet Union supported a single-party political system.
Step-by-step explanation:
The Soviet Union maintained as a form of government a one-party system, in which the Communist Party was the sole holder of public power. According to Article 6 of the Soviet Constitution, "the leading and guiding force of Soviet society and the core of its political system, of all state and public organizations, is the Communist Party of the Soviet Union. The CPSU exists for the people and serves the people".
Due to its central role in the Constitution of the Soviet Union, the Communist Party controlled all orders of government in the USSR and tolerated no opposition.