[Baron Munchausen]

Maybe, if you can get the fleet strategy to not attack targets that don't have weapons it will not attack further if the ground assault fails. Or maybe you'd have to have all the ships strategies set to not attack targets without weapons. Some experimentation with strategies will probably be necessary. It does seem to be a flaw if you cannot get the AI to try again rather than fry the planet for successfully resisting a ground assault. This might make sense for a nasty xenophobic type race, but doesn't make sense for most races. And what if the planet has something important that you want to capture? The automatic destruction is not just unthematic then, but plain stupid.