[dmm]

Maybe the weapons aren't targetting the population directly, but instead are taking out "soft" infrastructure, like power plants, water purification, refineries, factories, high-tech farms, etc. Sadly, we know from history that this kind of warfare can be devastating to urban populations. The more-advanced societies of SEIV might be extremely urban and therefore extremely susceptible to such warfare. The deaths from a DUC cannon would then be due directly to starvation, exposure, poisoning, disease, fire, rioting, etc., and only indirectly to the DUC. There might be a few hardy civilians able to survive in the wild, but not enough be worth counting. (Hey, there's an idea for a special race trait: Survivalists. Or maybe PhysicalStrength and EnvironmentalResistance could be used, making them much more valuable abilities.)