Who was the United States’ main rival during the Cold War?

Why this is the answer

The rival was the Soviet Union, officially the Union of Soviet Socialist Republics, or USSR. USCIS accepts three names for it: Soviet Union, USSR and Russia. The USCIS study guide explains the link with Russia: Russia and the countries it controlled were called the Soviet Union. What makes the rivalry striking is that the two had been allies. In World War II the United States and the Soviet Union fought on the same side. But the two countries did not trust each other. The Soviet Union was communist, and it controlled many nearby countries. The United States and its allies believed a democratic government and a capitalist economy were the best way to protect individual rights and freedoms. In March 1947 President Harry Truman asked Congress for aid to Greece and Turkey and declared that the United States would support free peoples resisting outside pressure. That policy, the Truman Doctrine, guided American foreign policy for the next 40 years. In the Cold War, American and Soviet soldiers never fought each other in battle. The two sides competed through diplomats and spies instead. Later Presidents used the reasoning of the Truman Doctrine to justify American action in Korea, Cuba and Vietnam. Their first direct nuclear confrontation came in October 1962, when American spy planes photographed Soviet nuclear missiles being installed in Cuba, about 90 miles from Florida. The rivalry lasted more than four decades. It wound down with the fall of the Berlin Wall in 1989 and the reunification of Germany in 1990, and it ended when the Soviet Union broke up in 1991. In the interview, be careful with China. It became communist during the Cold War, and North Korea did too, so both can sound plausible. But the rival on the list is the Soviet Union, under any of its three names.