For hypersonic missiles to work against ships, they require either nukes - in which case conventional ICBMs on a lower trajectory work fine - or terminal guidan

For hypersonic missiles to work against ships, they require either nukes - in which case conventional ICBMs on a lower trajectory work fine - or terminal guidance, which is an absolute bitch through 3000K plasma. There's a difference between being maneuverable and maneuvering to hit a moving target, after all. I don't think they change the naval balance of power much.