Lion's Pride by Anne McCaffrey

In this sequel to Damia's Children , the psionically Talented children of Damia Gwyn-Raven and Afra Lyon are pushed closer to the forefront of the struggle between the human Nine Star League and their alien Mrdini allies against the blind expansionism of the insect-like Hive culture that threatens both their civilizations. Rojer, like his siblings a T-1 at the most powerful level of Talent, is assigned to provide communication and transport for a squadron following a Hiver vessel. When he refuses a command by the Mrdini Captain Prtglm to launch missiles psionically against an occupied Hiver planet, he barely escapes while Prtglm kills his Mrdni companions, complicating an already delicate situation. A debate sharpens within the human community and with the Mrdini over the fate of the Hive colonies, with some humans and most of the Mrdinis holding out for complete destruction.