I love alternative history -- the what if exploration of what history might have been like if just one thing had happened differently. What if Genghis Khan had not died and thus the Mongol army had not retreated from the borders of Vienna? What if John Wilkes Booth had missed or What if Robert E. Lee had accepted a commission with the Union Army. Harry Turtledove has made a career out of these -- but I find them hit or miss.
Robert Conroy has written three alternative histories, and the latest, 1945, is an exploration of American and Japanese politics and military strategy. Here's the deal, the militarists in Japan seize Emperor Hirohito before he can surrender and the United States (with no help from its Russian Allies) is forced to proceed with the invasion of the Japanese mainland. As the casualties mount, support for the effort produces hawks and doves in America and political unrest rises. In Japan, desperate fanatics use desperate tactics to "protect" the homeland and repel the invaders. Real Japanese military patriots try to find a way to save their country from massive loss of life. American military commanders who now have men in the field try to minimize casualties while maximizing territorial gains -- and hold off the nuke 'em into the stone age factions. Add a couple of plot twists like a Japanese-American spy for the US who happens to find out where the Emperor is being held and a still active (and still arrogant) General MacArthur and you are off to the races.
I found the military strategy to be simply fascinating - and though I do not know how much real research Conroy did, it was pretty convincing to me. This was a quick, entertaining and quite interesting read. Have fun with it.