Ghost War — Michael A. Stackpole

A DARK AGE HAS DESCENDED...

For generations, the Republic of the Sphere has known a Golden Age of peace. Mighty BattleMechs, once kings of the battlefields, now aid the reconstruction of war-torn worlds. But when terrorists destroy the interstellar communications net, each planet is thrust into isolation. Suddenly old hatreds resurface and a people who have never known war face the prospect of learning its meaning firsthand.

Sam Donelly is one of the best ForestryMech jockeys on the planet, wielding his 'Mech's fifteen-foot chainsaw with the grace and precision of a surgeon. Caught in a skirmish with revolutionaries, he soon finds himself a rebel recruit. But Sam is no mere lumberjack, and if his true identity is discovered, the repercussions could be disastrous not only for Sam, but for the entire Republic....