The Accidental President: Harry S. Truman and the Four Months That Changed the World

This is the code name given to the effort to develop the atomic bomb over the course of World War II. German scientists had been the first to demonstrate the possibility of splitting an atom to release an enormous amount of energy. This prompted emigrés, most prominently Albert Einstein, to warn that the Nazi government could potentially develop a weapon of unprecedented capability. Fortunately, the Nazis made little progress in this space, in no small part because many of the physicists involved were Jewish, and therefore Hitler paid little attention to their ideas. Nonetheless, the United States undertook a multi-billion-dollar project to develop, test, and potentially use an atomic bomb. The project was under the joint leadership of US Army general Leslie Groves and theoretical physicist J. Robert Oppenheimer. The project resulted in the successful “Trinity” test of July 16, 1945, followed by the use of the atomic bomb over Hiroshima and Nagasaki in August of that year, but the project was also penetrated by Soviet spies, most notably Klaus Fuchs, who accelerated the Soviet development of its own weapon. The events of the Manhattan Project were depicted in the Oscar-winning 2023 film Oppenheimer.

The term “New Deal Democrats” describes the coalition of Democratic lawmakers and voters whose political ideology was shaped by Franklin D. Roosevelt’s New Deal policies. The New Deal included a broad range of social programs intended to ease the economic pain of the Great Depression by providing jobs for the unemployed and building a social safety net. Signal achievements of the New Deal include the Social Security System, the Federal Deposit Insurance Corporation (FDIC) that prevents people from losing their money when banks fail, and the Securities and Exchange Commission (SEC) that regulates financial markets. These policies increased the size of the federal government and gave it greater responsibility for the well-being of the American people. The coalition of New Deal Democrats included labor unions, urban political machines, universities and other social institutions, and the broad spectrum of voters who had benefited from Roosevelt’s more expansive vision of government. This coalition maintained power for decades, with Democrats holding the presidency from Roosevelt’s first election in 1932 until the victory of Dwight D. Eisenhower in 1952.

The third and final of the “Big Three” conferences held during World War II, Potsdam took place in a neighborhood of Berlin under the Soviet zone of control (all such conferences, the other two being Tehran and Yalta, were held in areas under Soviet control). With Roosevelt dying only a few months after Yalta, Truman was eager to establish his own relationship with his two counterparts, and address issues that he believed Yalta had left unresolved, especially the Soviet Union’s increasingly harsh control over Poland and other states that it had come to dominate in the wake of Germany’s defeat. Stalin and his Foreign Minister Vyacheslav Molotov insisted that these states be recognized as legitimate, whereas Truman, perhaps believing that he had a trump card, refused and then told Stalin about the imminent deployment of the atomic bomb. When Stalin did not register any surprise, Truman and his Secretary of State James Byrnes came to suspect that Stalin had already learned of the bomb through his own channels. While the conference did result in a proclamation calling for Japan’s unconditional surrender, its main outcome was to confirm the dividing line between the West and the Soviet Union.