All these certainly played a role in the outcome. But the debate between the candidates in the last months of that campaign was actually waged foremost around the real threat of a World War III with the Soviet Union over the-then heated crisis in Berlin. The Soviet blockade of allied-occupied sectors of Germany's capital, and the allied airlift in response, dominated newspaper headlines. The candidates' stump speeches were an exchange of vicious accusations about which party's policies presented the greater threat of leading to a communist-dominated world. On September 25, 1948, the Soviets rejected a final allied plea to lift the blockade, and the issue was pushed to the United Nations in what was seen as the last step before a decision to go to war.

It was in this context that Truman summoned the poker buddy he had installed as chief justice of the Supreme Court, Fred Vinson, to the White House on October 3 and asked him to meet with Stalin face-to-face to offer a message of peace in the hope of bringing the Cold War to an end. It would be the highest-level exchange between the countries since Potsdam at the end of World War II. Though Vinson protested that he had no more knowledge of the situation in Berlin than what he had read in the newspapers, had no experience in foreign policy, and feared violating the separation of powers by undertaking a high-profile, highly political task just a month before the election, he eventually agreed when Truman argued that it was Vinson's patriotic duty to help avert war.

Truman told his press secretary, Charlie Ross, to secure a half-hour of nationwide airtime for a special announcement from the White House on the night of October 5. Ross did so, swearing the broadcasters to secrecy. Truman's speechwriters prepared an address to the nation that ended with a lofty pledge to solve the Berlin crisis: "We shall spare no effort to achieve the peace on which the entire destiny of the human race may depend." But despite all the activity, the rest of October 3 and October 4 passed with Truman neglecting to inform any of his foreign-policy advisers or any other allied nation's leaders about his plan.

On October 5, Robert Lovett -- the under secretary of the state who was running the department while Secretary George Marshall was engaged in direct negotiations with the Soviets in Paris -- was at his desk in Foggy Bottom when an aide walked in with a draft of Truman's message to Stalin that had been received in the code room. Lovett could scarcely believe his eyes. He picked up the phone and called the president, asking to see him at once. When Truman invited him to come right over, Lovett ran downstairs to his black official car and, for the first time ever, he asked his driver to turn on the car's siren and flashing red lights and speed to the White House through the streets of Washington.