To what extent was Soviet expansion responsible for the outbreak of the Cold War in Europe?

To what extent was Soviet expansion responsible for the outbreak of the Cold War in Europe?
I believe that Soviet expansion was one of the main factors for the outbreak of the Cold War, there are other factors to consider as well which puts the blame on America as well, but the Soviet’s spreading their message of communism into other countries post WW2 was the main reason.
By early 1946, the Soviet Union had tightened her control over Eastern European Countries. Stalin had started to promote communism in the region and tried to consolidate the communist rule in Bulgaria, Rumania, Hungary, Czechoslovakia and Poland. During the elections, communism lost most of them. However, Stalin forced the countries to be ruled by a communist government and a one party dictatorship was set up in these countries. They became the Soviet satellites. This made the western side felt suspicious. At first, Yugoslavia was also on of the satellites, however, in 1948, she left the Soviet bloc. Marshal Tito was able to maintain a communist government in Yugoslavia, which was independent on Moscow. The spread of communist control in the east made the capitalists in the west think that their democratic policy was being threatened. This Soviet expansion in East Europe also worried the U.S who (under Truman) decided to take action to stop the Soviet expansion by introducing the Truman Doctrine in 1947. At that time, British could no longer afford to help the anti-communist forces in Greece which Britain warned would turn communist if the USA did not step in. Truman’s policy was made clear in his speech to the American Congress in March 1947 that he was determined to act positively to prevent the Soviet Power from advancing further a field. The American help would be mainly in terms of economic and military aid. This meant the Greek government was able to defeat the communists. The civil war was finally ended in 1949 and the success of Greece in resisting the communist threat was seen by the West as a victory of the capitalist bloc over the communist bloc. But Truman still felt that communism was particularly attractive to poor and discontented people and it could best be resisted by economic prosperity, therefore, he thought that a prosperous Europe with close commercial links to the United States was less likely to fall under communist influence. It was under this consideration that in 1947, the United States offered a massive package of economic aid to Europe. This was the “Marshall Plan” announced by George Marshall, the American Secretary of State. The plan was intended to bring the economic recovery off Europe so that she could resist communist expansion. It was offered to Western as well as Eastern Europe. However, Stalin thought that the Marshall Plan was a plot of the capitalist to dominate Europe economically and politically and wasted in no time in using its veto at the United Nations to stop any attempt to weaken the Soviet position. So she prevented her satellites in Eastern Europe from accepting the Marshall by setting up the Communist Information Bureau. It was formed to co-ordinate the activities of the communist parties of the Soviet Union and her satellites. This was the expansion of the USSR and the Americans did not like it.
