Thinking of individual ants is really the wrong analogy; ant colonies are more like the organism. Your hands work on instinct too (just look at newborn babies; they can do very little, but they can grab things).
I'm not saying ants/ant colonies don't exhibit intelligent/sophisticated behavior, but we don't have evidence to suggest they understand the higher order consequences associated with where they build their colonies.
For similar reasons, we don't consider it murder when an apex predator kills a human, but we do when it's another human.
> Your hands work on instinct too
The operation of many (if not most) of the systems in our bodies is instinctual and a mystery to us from a 1st person perspective, e.g. we don't actively beat our hearts, digest our food, etc. But continuing the last point, if you used your hands to cause harm to another human, "my hands work on instinct" isn't a reasonable defense. We still have agency and the ability to choose how we use our hands, and we're (generally) aware of the consequences of the actions we facilitate with our hands, even if we aren't directly aware of how our hands function.
