This is probably Herbert's least well known novel, but it's a remarkable tale of a futuristic submarine war and what sub technology and tactics might be like in the future. As in his most famous novel, Dune, people and technology are often mere chess pieces in a greater political game. In Dune, despite their advanced knowledge of cognitive psychology, human abilities, and psychophysiology, the characters are controlled by the Machiavellian vicissitudes of their everyday lives. This book shows Herbert already thinking about the implications of the philosophy he was to develop more fully there.
In his short story, Cease Fire, published ten years before Dune, we see Herbert's fascination with Machiavelli and with political intrigue and psychological warfare. This interest was to combine with his interests in ecology, psychology, and technology to produce his famous masterpiece, Dune. Overall this is another fine Herbert novel and one that deserves to be better known and that presages much of his later important work.