Old Soldiers 
Captain Maneka Trevor was the sole human survivor of the Dinochrome Brigade's 39th Battalion . . . but she hadn't wanted to be one. The Bolo known as "Lazarus" -- Unit 28/G-179-LAZ -- was the 39th's sole surviving Bolo . . . but he hadn't been hers. The doctors and the Bolo techs have put them both back together again, yet there are wounds no doctor or technician can heal. And now Maneka and Lazarus must serve together once again, in a war whose stakes are literally the survival or extermination of the human race. They are all that stand between a desperate, secret colony of humanity and destruction: a Bolo commander torn by survivor's guilt and a Bolo whose very existence reminds her of all she has lost. The odds against them are heavy, the stakes are huge, and surrender is not an option. The Dinochrome Brigade is used to that, but can Maneka and Lazarus survive their own shared past to defend the present?
Reviews
I hope that Weber does more novels in the Universe. The only other author that really bring the Bolos to life is William H. Keith, who has written the most full length novels in this series.
If you are a fan of the Bolo Novels and Short stories or if you are a new reader to the series, you will not be disappointed.
The hero of this novel is the supertank and the heroine is the tank commander.
By the time the fighting (which is very well done) is over the two have "A LOT in common" to say the least. To tell much more would give away too much of the story, but I highly recommend it to Weber SF readers and to anyone who likes Military SciFi.
A pair of obsolete Bolos, a small fleet, and the transport ships of a new colony set off for a new world--somewhere in space. But Melcornia has calculated that the humans will try such a ploy and an Empire fleet discovers the colony task force--and attempts to destroy it. Destroying a Bolo, though, is harder than it looks--and a Bolo looks hard. The Bolo is a monster on land, but even in space, its weapons are as powerful as anything mounted on a cruiser.
Their warships destroyed, a Melcornian troopship tracks the colony transports to their new world and attacks. Their plan should have worked--but once again, it's impossible to overestimate the power of a Bolo.
Author David Weber approaches Bolo warfare with the same mathmatical precision he uses in his Honor Harrington series. Throw weights, percentage of projectiles that self-destruct, damage from electro-magnetic impulse, and the rest are all calculated and displayed for the reader's benefit. Also as with the Honor Harrington series, a clever female soldier (Captain Maneka Trevor in this case) is able to outthink and outplan her enemies to a hopeless degree (although was it really necessary--she had a Bolo)?
Weber makes OLD SOLDIERS work by making the Melcornians the true protagonists. Like Lucifer in Paradise Lost, the Melcornians know that they have no chance of victory. The Bolo will simply grind them into nothingness. Still, they are resigned to doing their best, to doing what they can in hopes that some miracle may spare them--when their entire fleet, and indeed their entire race, was destroyed by the Bolos.
On its face, OLD SOLDIERS is another paen to mass murder--certainly the apparent protagonists never really think about the deaths they're inflicting. But beneath the surface, Weber has created a strong anti-war statement. The Melcornians and humans are essentially indistinguishable--both facing destruction at the hands of an enemy they can't understand. Both pursue honor, duty, and believe that they are waging an essentially defensive war. By the end, only a truly disturbed reader will want to hear about another mass of death.
