The relationship between the u.s. and the Soviet Union changed after WWII when the soviet union began to become more dominant. they started advancing faster than other countries, and the u.s. took it as a threat. the u.s. was also against communism, and the soviet union wanted to spread it.
U.S.-Soviet<span> Alliance, 1941–1945. Although </span>relations between<span> the </span>Soviet Union<span>and the </span>United States<span> had been strained in the years before </span>World War II<span>, the </span>U.S.-Soviet<span> alliance of 1941–1945 </span>was<span> marked by a great degree of cooperation and </span>was<span> essential to securing the defeat of Nazi Germany.
i know this cause i took it 2 years ago so yea hope this helped =)
Gorbachev brought perestroika to the Soviet Union's foreign economic sector with measures that Soviet economists considered bold at that time. His program virtually eliminated the monopoly that the Ministry of Foreign Trade had once held on most trade operations.