The two superpowers of future Earth had learned to fight their wars
among the colonized planets rather than on the home world – and if they
could do it with paid mercenaries, so much the better. The best were
the men of the Dorsai, soldiers born and bred, who commanded the
greatest military respect.
But in the battle going on on Kultis, something extra was involved. A very personal contest between the brash theoretical tactician, Cletus Grahame, for the Western Alliance, and his challenge to the most ambitious statesman of the Eastern Coalition. Grahame was no Dorsai, but he did have a set of untested theories, a style of physical wizardry, and what he called the "tactics of mistake."
And the novel of how Grahame risked his life, the fate of three worlds, and ultimately the whole of the Dorsai to find out whether a mistake was not a mistake, is one of the most, consistently exciting science fiction novels of the year.