Dropping a couple hundred Tsunamis or whatever the predecessor for them was (surely there were bombs before the Tsunami, the idea that there weren't is patently absurd considering that the Vasudans had them long enough to build at least two generations of bombers) would kill pretty much everyone on Vasuda Prime immediately and condemn any survivors to a slow, lingering, horrible death. Our hydrogen bombs are like firecrackers compared to what the FreeSpace universe considers weapons of mass destruction. The target world might not be made fully melty and airless like a Base Delta Zero, but there wouldn't be any sapient beings left when it was all over.