X-Day: Japan and Kyushu Diary are works of fiction, though based on substantial research into historical facts and documented plans. All characters outside of prominent historical figures and celebrities are fictitious. All actions and statements by the characters are fabricated for purposes of the story. Most ships mentioned in the book are permanent museum ships.
It is explicitly not the point of this work to predict the path of history given one change in the timeline. If anything it is to tear up the notion of a “timeline.” Events in human affairs are highly volatile and sensitive to subtle influences. The only thing which is inevitable is that surprises will happen. History is a tree, not a vine.
Alternative histories are usually presented with a ‘hook,’ right up front on the cover. This story is presented from the perspective of individuals who have no access to high level decisions or plans. They are oblivious to the hook. Make what you will of the suppositions that support this alternative history. The contrived result is that the invasion of Kyushu went forward roughly as it was planned by the beginning of August, 1945.
Both sides had much time to adjust between the historical fork of August 6, 1945 and the invasion start. The Japanese could make deeper and different fortifications on Kyushu. The Americans would have had to deal with setbacks from the string of typhoons that hit the southwest Pacific. Assumptions about those actions and responses were made to support the fiction, not to advance any historical theory.
Tuttle’s goal in his original columns was to educate readers in the U.S. about the war in the Pacific, after most had been fed headlines that focused on Europe until fighting there ended in May of 1945. That mission remains active. Every year web traffic spikes in early June as people read up about D-Day and watch Saving Private Ryan. A select few take time to remember names like Taffy-3, Midway, Tarawa, and the myriad non-Normandy D-Days (even after they dropped the D).
This story may also appeal to those involved in the debate about use of nuclear weapons on the cities of Hiroshima and Nagasaki. Many have said “We should not have bombed the cities.” A more thoughtful few have asked, “What if we didn’t?” Deciding not to drop them on cities does not a) end the war, or b) make the atomic bombs go away. A complete argument includes acknowledgement of alternatives, be it millions of Japanese starved to death in a blockade, or a million battle deaths from invasion, or a muddled resolution that leads to years of conflict and political tension. And the bombs would still be there at the ready, making a first use inevitable whatever the circumstance. X-Day: Japan explores a tactical military use of the weapons.
The plans for Operation Olympic, the invasion of southern Kyushu were developed and refined over the course of 1945. Also evolving over that time was intelligence about the strength of Japanese forces on Kyushu. The Japanese, using the same maps and basic knowledge as the Americans, predicted precisely where the American landings would be, and began to make defenses accordingly.
Based on reading from multiple sources, on both sides, about the fighting on Okinawa and Iwo Jima in particular, it was assumed that Japanese resistance would be not just determined, but professional, coordinated, and competent. American forces would land outnumbered into highly defensible terrain. The whole battle was gamed out twice to support the book. Casualties were severe on both sides no matter the game parameters. And that’s before the long battle line was nuked, with gruesome and unforeseen consequences.
One contingency in the invasion plans was the availability of seven or eight atomic bombs by November 1945. The starting point for this book as a theoretical exercise is that bombs were not dropped on cities, but instead held back for tactical military use. Some other author might write the book about how MacArthur found out about the first test and then convinced the select few in Washington D.C. who knew about them to save the bombs for military use. [This is hinted at in one of Tuttle’s entries from San Diego.]
When he was ten years old, Shawn D. Mahaney found Guadalcanal Diary in his grade school library. He also grew up reading Sgt. Rock comics, and wished old Easy Company would have got to fight the Japs.