Here are some reasons why Roosevelt may not have been able to single-handedly prevent the Cold War:
Differing Postwar Objectives: Roosevelt and his Soviet counterpart Joseph Stalin had different visions for the postwar world. While Roosevelt sought to establish a global system based on collective security and economic cooperation, Stalin was focused on securing Soviet security and expanding its sphere of influence in Eastern Europe.
Ideological Differences: The United States and the Soviet Union represented opposing ideological systems, with the US advocating for capitalism and democracy, and the Soviet Union promoting socialism and communism. This ideological divide made it difficult to find common ground and compromise.
Personal Tensions: Roosevelt and Stalin had a cordial but tense relationship. Their communication was often indirect, and they had conflicting personalities and leadership styles. This made it harder for them to establish trust and rapport, which could have facilitated collaboration.
Yalta Agreement Controversies: The Yalta Conference in February 1945, where Roosevelt and Stalin met, resulted in agreements on dividing postwar Germany and Eastern Europe. However, these agreements were later criticized as giving too many concessions to the Soviet Union, fueling resentment and increasing tensions.
Rising Soviet Ambitions: Even if Roosevelt had pursued more conciliatory policies, Stalin's ambitions to extend Soviet control and influence in Eastern Europe and beyond were a significant contributing factor to the Cold War.
It's important to note that the Cold War was a multifaceted and protracted historical event that involved multiple actors, interests, and developments over several decades. While Roosevelt certainly played a significant role in shaping international relations during his presidency, the occurrence of the Cold War cannot be attributed solely to his actions or decisions.