An interesting military SF novel about mechs, alien invasions, but most of all the time loop that Keiji is caught in. He lives the same battle and the same death over and over, trying to get out of the loop. While the story has its moments, there is too much emphasis on the battles for my taste. The last chapter takes a surprisingly sentimental turn. Most of all, what this novel made me realize is how little I know of the Japanese SF tradition. I feel that there is more going on here, that I am simply not attentive to, because I am not aware of the tradition.