The discussions and debates went on for quite a time, as these things tended to do in the Culture, but the result was just what the Mind of the Kainotophilist had anticipated. An significant majority of the people - humans and drones - on board supported the idea of engaging the Hegswarm with the intention of wiping from the face of the galaxy, realising that this meant putting themselves on the line to protect other life in this galaxy.
A large-ish minority argued that the Kainotophilist and its crew might just be the last survivors of the Culture - the ship was forced to admit that it had had no communication with anybody in their old galaxy for a very long time. Therefore, the argument went, it would be irresponsible to throw away their own existence on a moral crusade; rather, it was imperative that they used their resources to preserve and rebuild the Culture here, while they still had a chance to do so.
The compromise finally reached was a split: one of the LSVs the Kainotophilist had constructed agreed to act as a lifeboat for those people and GCUs who elected to retreat and rebuild elsewhere in the galaxy. The LSV immediately renamed itself the Survival Planner, eased its way from the Mainbay where it had been constructed and immediately started moving aboard everybody who wished to leave. The Kainotophilist encouraged everybody to have backups made - a snapshot of what in another era would have been called a person's soul - and distributed those recordings aboard the LSV and its GCUs for safe-keeping.
In three days, the Survival Planner was ready to go; the intervening time had been busy for everybody, with numerous goodbye parties, receptions, gatherings, event, orgies and general knees-ups to wish those leaving, and those staying, the very best of luck. The actual departure was muted, possibly because almost everybody was still recovering from the excessive partying. This was a very Culture way of doing things.
The Survival Planner was headed for a part of the galaxy furthest away from any known infestations of Swarm Objects. Out of an abundance of caution, it chose not to inform the Kainotophilist of its exact route it intended to take. Similarly, the Kainotophilist declined to give any information on how it proposed to engage the Hegemonising Swarm until the Survival Planner had long departed.
A Culture Mind was millions of times smarter and thought millions of times quicker than any human, so it was entirely reasonable that it would prepare individualised briefings for every one of the humans and drones aboard. Keraki Nlissa could have imagined that the ship was speaking to her alone, although she knew that just about everybody would be getting told what was going on at a level of detail tuned to their personality and interest.
"Ship, please tell me about these Hegemonising Swarm Objects," Keraki Nlissa said. She had settled herself in a state of calm and sober attentiveness, aided only a little by several glanded substances, and was sitting in the small quiet room she had long taken to use as her study.
"Weeell," the ship began, sounding exactly as if it were just pulling together an impromptu speech, "I’ve been studying this Swarm remotely for quite some time. Individual Swarm Objects don't have the ability to move very far in hyperspace, nor do they seem capable of using Artificial Gravity in any form, and they don't seem to be particularly smart, either."
"They're not moving at super-luminal speeds?" Nlissa demanded, "Surely that gives us a considerable advantage?"
"It does," the ship confirmed, "But are managing significant real-space acceleration using some form of reactionless drive. Being machines, they can tolerate accelerations which would turn a human into a thin smear of red paste."
"So what's the problem?"
"Individually, no problem," the voice of the Kainotophilist said, "Swarm Objects could just be blown up. A small-scale CAM or AM nano-warhead would be quite enough to turn any single object into a rapidly-expanding cloud of hot plasma. The problem was that there are just so many of them. A thousand GCUs each discharging a thousand nano-warheads a second would take three thousand years to destroy all the Swarm Objects currently in this galaxy, and naturally they would be creating even more during those years."
"And the ships would have to concentrate for every second of those three thousand years. A moment's inattention might allow an unnoticed Swarm Object to bypass a GCU's hull-field structure, even when it was in hyperspace, and attach itself to the fabric of the ship itself. A GCU would probably notice, of course, but if its attention was being distracted by millions of other Swarm Objects, it might be compromised before it realised."
"It's a numbers game?"
"Yes," the ship confirmed, "So we have to be quite a lot smarter about our approach."