One of the ways that alternate history novels can be classified is by dividing them into two categories. The first consists of alternate history novels that are descriptions of major events told through the actions of the characters, historical or fictional. Most works of alternate history (such as those by Robert Conroy, Peter Tsouras, and the increasing majority of Harry Turtledove's novels) fit into this first category, in which the events are the focus and the characters themselves are primarily used to tell the story. The other, far less common group of alternate history novels are those in which the focus is on the characters rather than the events, with the authors of those works using the altered setting primarily as a different stage in which their characters develop in response to circumstances other than those dictated by history.
Alfred Coppel's novel is one of that minority of alternate history novels in the second category. In it, he uses the disruption of the Trinity test by a storm as a premise for the launching of the Allied invasion of Japan that was in real life rendered unnecessary by the Japanese surrender that the atomic bombs provoked. Coppel skips over Operation Olympic -- the invasion of the island of Kyushu in November 1945 -- to start with the much larger Operation Coronet, the invasion of the main Japanese island of Honshu, in March 1946. It is within this dramatic backdrop that his narrative unfolds, with American and Japanese characters facing the prospect of death in a titanic final clash between the two sides.
As both a longtime author and a fighter pilot during World War II, Coppel captures effectively the elements of combat within his narrative. But it is with his character development that his novel truly shines. He focuses on about a dozen main characters, using their particular experiences over a series of chapters to describe what the horrors of such an invasion may have been like. Even with his secondary characters, the space he takes to explain their background (an effort that never feels awkwardly shoehorned into the novel) pays off by imparting a real importance and poignancy to even their most mundane activities. All of them share in the stress of battle, and though his three main characters (an American Ranger who grew up in Japan, his Nisei subordinate, and their Japanese opponent who happens to be the childhood friend of the first character) seem a little too conveniently situated, overall they help convey the tragedy and insanity of the war they experience. It all makes for an alternate history novel that is far superior to most of the alternate history works turned out today, the overwhelming majority of which would be much better if they followed Coppel's example and concentrated on the people rather than the events, no matter how exciting those events may be.