Other way to hit battleship safely with firestorms is with 2 fusion missiles. Hit it until all missiles (4 in this matter) run out, then pull back. Well, fusion missiles cost elerium, I know, it's expensive. But you don't really need 500 eleriums in your base right? I think the safe number is 100. Oh yeah, don't even think about using it on interceptors, they're too slow to chase battleships