The firestorm, I am pretty sure, was not purely intentional. I don't think they could have predicted the degree to which the winds would have generated the inferno that resulted. Sure, they set out to burn some buildings. But I doubt they knew the Dresden firestorm was even possible beforehand, much less intended it to happen. Of course, I don't have access to all the information on the Dresden raids, so you're more than welcome to correct me if I'm wrong.
