"Well, of course they are, Captain." Houseman's tone was just short of impatient. "But the best way to do that is to settle the locals' differences. The potential for instability and Havenite interference will remain as long as their hostility does, whatever else we may accomplish. Once we bring them together, however, we'll have two friends in the region, and there won't be any temptation for either of them to invite Haven in for military advantage. The best diplomatic glue is common interest, not simply a common enemy. Indeed," Houseman sipped his wine, "our entire involvement in this region stems from our own failure to find a common interest with the People's Republic, and it is a failure. There's always some way to avoid confrontation if one only looks deep enough and remembers that, in the long run, violence never solves anything. That's why we have diplomats, Captain Harrington—and why a resort to brute force is an indication of failed diplomacy, nothing more and nothing less."
Major Tomas Ramirez, commander of Fearless's Marine detachment, stared at Houseman in disbelief from further down the table. The heavyset, almost squat Marine had been twelve years old when Haven conquered his native Trevor's Star. He, his mother, and his sister had escaped to Manticore in the last refugee convoy through the Manticore Wormhole Junction; his father had stayed behind, on one of the warships that died to cover the retreat. Now his jaw tightened ominously as Houseman smiled at Honor, but Lieutenant Commander Higgins, Fearless's chief engineer, touched his forearm and jerked a tiny headshake. The little scene wasn't lost on Honor, and she sipped her own wine deliberately, then lowered her glass.
"I see," she said, and wondered how the admiral tolerated such a nincompoop as his second in command. Houseman had a reputation as a brilliant economist and, given Grayson's backward economy, sending him made sense, but he was also an ivory-tower intellectual who'd been plucked from a tenured position in Mannheim University's College of Economics for government service. Mannheim wasn't called "Socialist U" for nothing, and Houseman's prominent family was a vocal supporter of the Liberal Party. Neither of those facts were calculated to endear him to Captain Honor Harrington, and his simplistic notion of how to approach the Grayson-Masada hostility was downright frightening.
Book is David Weber's The Honor of the Queen
+1 to PoG being a better entry point to the series than Consider Phelbas