Raven's Flag - Glynn Stewart - Bog

In times of peace, alliances wither and are forgotten.
In times of war, honor must reforge them in fire and steel!

The United Planets Alliance fought the Kenmiri Empire with a hundred allies at their side. Bound in common cause until genocide broke the Kenmiri-and Kenmiri schemes broke the alliance in turn-those one-time allies still left deep debts of blood and friendship behind.
Still, the UPA has forged ahead in the post-Kenmiri times, weaving new economic and military alliances despite their more limited reach. The last thing they are expecting is for a soldier of the Londu, one of those half-forgotten allies, to arrive in Sol itself and ask for help.
An unknown alien force, armed with weapons thought unique to humanity, has assaulted the Londu people. To honor debts and promises alike, Rear Admiral Henry Wong and Ambassador Sylvia Todorovich find themselves called to take a fleet farther than any human ship has gone in half a decade-and challenge an enemy they know nothing about.
If the Londu are even still there when they arrive...