Roosevelt, commonly known as FDR, had the leadership skills to guide the US through the Great Depression of the 1930s and most of World War II. He's also the only president to serve more than two consecutive terms in office – managing to secure a fourth term before he died in 1945.
Franklin D. Roosevelt was justified to run for more then two terms because at the time world war 2 had just begun and during the election the United States was having a Great Depression. Timing was the excuse, these two problems justified Franklin D. Roosevelt’s 3rd re-election
In short words, many things triggered the cold war, but personally, I think the main event would be the splitting of Germany. one side democracy (USA) the other side Communist (USSR)
Nationalism helped Germany become more unified and it helped establish a sense of culture. It also helped Germany get a tougher military force so that it could protect itself from outside problems