Any spacefaring nation with propulsion technology sufficiently powerful that interstellar voyages are feasible... basically have technology that can sterilize planets. It's called "pointing the drive in the wrong direction."
Hopefully, any spacefaring nation smart enough to develop sufficiently powerful propulsion is also smart enough not to casually commit xenocide with it. Given our own track record, though, that's a pretty freaking big "hopefully."
Hopefully, any spacefaring nation smart enough to develop sufficiently powerful propulsion is also smart enough not to casually commit xenocide with it. Given our own track record, though, that's a pretty freaking big "hopefully."