We're not talking about millions of civilians getting murdered on a populated planet, we're talking about hundreds of military and or corporate personnel being killed on a strategic military and or economic asset after the opportunity to evacuate has been given. Such attacks are a means to an end, and can't be compared to our modern sensibilities about mass destruction (not that it really applies, anyway). Also, you still haven't answered why any house militaries or unlawfuls would care, especially if weapons of this nature could cut costs and manpower required to down a base.
