— Consider this fictitious scenario: In the summer of 1950, President Thomas E. Dewey faced a national security crisis of extraordinary proportions — one that his advisors agreed likely would define his presidency. After beating his Democratic opponent in 1948 by a comfortable margin, Dewey received news that Soviet-backed armies in Korea, Hokkaido, and Northern Honshu had mounted a massive invasion of Southern Honshu, with the goal of unifying Japan under a single government. He knew that American occupation forces — under strength, dispirited, and still fighting insurgencies loyal to the emperor in Kyushu and Shikoku, as well as other scattered parts of the former Japanese empire — were hardly in a position to resist.

Although he based much of his election campaign on a “Truman Lost Japan” platform, he now lamented the fact that the war dragged on through the spring of 1947 instead of ending in the summer of 1945. That brought in the Russians, who took over all of Korea and carved out an occupation zone in northern Japan, transforming it into one of their notorious “people’s republics.” The United Nations could do nothing — the Russians had the veto — and Americans were sick of war. What was the United States going to do? Use atomic bombs to stop the invasion? Unthinkable! Especially not with the Russians also having tested an atomic weapon during the previous fall.

The new American president slumped in his chair in the oval office, disconsolate — and angry. China, Russia, Korea, and now probably Japan — all communist dictatorships. Where else would Joe Stalin press his advantage? In Europe again, against Germany? Central Asia, perhaps? Iran? Pakistan? Victories whet imperialist appetites. And America was losing the Cold War. If only that novice Harry Truman had acted as tough as he talked…

Of course, the fact that Truman did, spared us this nightmare version of an early Cold War alternative history. In fact, in the months leading to the actual surrender of Japan, which occurred on Aug. 14, 1945 (Washington time), a variety of morbid statistics on estimated casualties haunted the president’s thoughts. On Okinawa alone, American casualties ran to 75,000. And a horrendous battle it was — replete with flamethrowers torching caves filled with suicidal Japanese soldiers and terrified Okinawan citizens, tanks attacked by enemies with bombs attached to their heads, endless mortar and artillery bombardments — it was the worst battle in a war that had also included Guadalcanal, Tarawa, Iwo Jima.

Then there was the kamikaze. From April 6 to June 22, when the island was finally declared secure, the Japanese staged 10 big attacks involving 1,465 aircraft, inflicting tremendous damage, in terms of ships sunk, lives lost, and morale depleted. Indeed, historian Max Hastings notes in his superb account, “Retribution,” that “For the sacrifice of a few hundred half-trained pilots, vastly more damage was inflicted upon the U.S.  Navy than the Japanese surface fleet had accomplished since Pearl Harbor.” What was the number of aircraft available to Japan to defend the home islands against an American invasion? Answer: 10,000. Half of those were kamikaze. That’s not to mention suicide boats, human-torpedoes, human-bombs, and swimmers with bombs.

No doubt pondering this information worsened the soul hollowing-out nature of casualty estimates for an invasion of Japan, which President Truman had been receiving since August 1944. The most recent figures from the last week of July 1945, were provided by General George C. Marshall and entailed the loss of anywhere from a quarter million to one million Americans. Likely, Japan would lose all of its nearly three-quarter-million man army in the region, along with millions of civilians. For numbers like these, the word “intolerable” barely gnaws on the edge of one’s imagination.

Which of course brings to mind the way the war actually ended, with the dropping of two atomic bombs, the Russian invasion of Manchuria, Emperor Hirohito’s dramatic radio message to his people, and the signing of the surrender terms on the USS Missouri in Tokyo Bay on Sept. 2, 1945. In the final analysis, by the emperor’s own words, it was the atomic bombs, and not the Russian invasion of Manchuria, that forced the issue: “The enemy has begun to employ a new and most cruel bomb, the power of which to do damage is indeed incalculable, taking the toll of many innocent lives. Should we continue to fight, it would not only result in an ultimate collapse and obliteration of the Japanese nation, but it would also lead to the total extinction of human civilization.”

So the greatest war in history finally came to an end. And not just to an end, but to the best conclusion that could be expected, considering the circumstances. And for the millions of lives, Americans and Japanese alike, saved by Truman’s decision, no better expression of relief can be found than in the words of notable historian and former combat soldier, Paul Fussell: “For all the practiced phlegm of our tough facades we broke down and cried with relief and joy. We were going to live.”

Thanks to him, President Truman, and millions of other brave men and women, so are we.

 (Folkertsma is a professor of political science and fellow for American studies with The Center for Vision & Values at Grove City College in Pennsylvania. The author of several books, his latest release is a high-energy novel titled “The Thirteenth Commandment.”)