Please read what you wrote again. Since when in the history of cruise missiles have geographical features ever served as any sort of protection against cruise missiles attack?!
Natural, LoS blocking terrain features frigging aid cruise missiles, not hinder them, which is why cruise missiles literally go out of their way to hug any and all LoS blocking terrain they can to try to delay radar detection.
Having the naval base clear of LoS blocking terrain is done precisely to help protect it from cruise missiles attack, since they will have no terrain to hide behind on approach to maximise the defender’s radar detection range and reaction/engagement time.