Between the military gung-ho enthusiasm of Starship Troopers and the Vietnam influenced cynicism of The Forever War, the field has been covered by some of the very best sci-fi works. That provides a big challenge to the first time novelist (as Scalzi was at the time).
The book shows some early promise, with a nice twist on the usual military induction clichés by having a future where it is pensioners who get enlisted (medical advances can give them back their health and pensioners have years of experience to call on). Moreover, the secrecy, scale and advanced features of the military’s technology evokes a sense of mystery about quite who the Colonial Defence Forces are, what they do and why.
However, these promising starts are not followed up. Most of the mystery quickly falls away and for much of the book it is just an incidental detail that enlistees are pensioners. They don’t feel and sound any different from the characters in books where the military inductees are teenagers. The plot sees many of the standard clichés of this genre played out, though without the inventiveness of military tactics seen in books such as Ender’s Game or Tactics of Mistake.
There are also a couple of very weak spots – the claim that “No army ever goes to war with more the bare minimum it needs to win” is particularly odd from an American author given that country’s military doctrine – and the utterly implausible coincidence on which the later half of the plot hinges takes place not merely once, but twice.
And yet… this is not a review that will conclude you should not read the book. Yes, it isn’t a Starship Troopers or a Forever War and yes it has its weaknesses, but in between the story is lively, has some good jokes, moves along at a fast pace with some moments of real tension and keeps the military detail to the necessary minimum. It is a story set amongst the military, not a eulogy to military detail. And Master Sergeant Ruiz may fulfil every cliché of an officer put in charge of recruit, but he does so knowingly – making the character very funny and great fun. If the book is made into a film, the right actor in that role would completely steal the show.
Moreover, the plot does raise some deeper questions about colonialism and the role of the military. Superficially, the colonising military industrial complex are the good guys and it is right to kill aliens and colonise planets. But there are more than enough hints in the book to doubt their good guys persona (and indeed that is a theme returned to later in the series).
So all in all, if you have already read the classics of this genre, Old Man’s War is a good read to turn to next.