Yet another damn good book that shouldn't be out of print, Wil McCarthy's Aggressor Six is not only one of the best first contact stories I've ever read, it's also one of the very best first sf novels. It combines the well-worn military sf idea of a war against a spacefaring insectoid foe, a la Starship Troopers and Ender's Game, with the badly-neglected idea of humans trying to understand and communicate with an alien race which thinks as intelligently as we do but differently.
McCarthy's insectoids, the Waisters, are far more advanced technologically than the spacefaring humans and are systematically wiping out our colonies, even though we apparently pose little threat. The heroes aren't trying to retaliate: they're trying to tell the Waisters that we don't want to fight. We're trying to surrender before we're made extinct.
The 'Aggressor Six' of the title is a group of five people and a Martian retriever trying to simulate, and thereby understand, the behaviour of standard Waister fighting team: a Queen, two workers, two drones, and a 'dog'. The most recent recruit is Marine Corporal Kenneth Jonson, a hero (e.g. one of the few survivors) of the 'Flyswatter' operation, a raid on a shattered Waister scoutship. Jonson, who has seen the Waisters raze his native Albuquerque, uses implants and equipment to help himself see and vocalize like a Waister. Wracked with post-traumatic stress and living in a recreation of a Waister ship as well as a Waister social unit, he throws himself into the nightmarish task of trying to think like the enemy and work out the reasons for their genocidal and apparently illogical strategy.
Increasing the tension, the Waisters have just killed another seven million humans on one planet and are headed for the system where the psyops team is stationed, the commander in charge of the project thinks it's a bad idea and is trying to isolate them, and most of Jonson's team-mates suspect he's going crazy.
Intelligent, taut and fast-paced, with an advanced technology that I found utterly convincing (McCarthy is Chief Technology Officer for Galileo Shipyards, an aerospace firm), the novel had me completely hooked as soon as I met Shenna, the voder-equipped dog, on the second page. And I'm a cat person.
Apart from Jonson, xenobiologist Marshe Talbott (the six's 'queen') and the rigid Colonel Jhee, the rest of the characterisation is pared back to a minimum, but this fits the economical style and the claustrophobic tone of pressure and urgency. And the depiction of the scientific process is so interesting that even if the survival of the human race didn't depend on the six finding a solution, it would still be a riveting novel for those of us interested in well-crafted puzzles.
It amazes and saddens me that this excellent book is out of print, unfilmed, and so little known. If you see a copy, grab it.