actually modern "nimble" crusiers are slower and not much more manuverable than the Iowa class BBs.

Plus when reagan ordered the recomm. the ships were extensively upgraded with new electronics and self-defense such as Phalanx guns.
There was a project for 11" sabot rounds fired from the 16" guns which would extend their range to 100 nautical miles (more than the Harpoon cruise missile) also the rounds would be radar and laser guided.
Also the 23nm range of the standard 16" HE shell is plenty for supporting Marine landings

think about it, would you waste a cruise missile or expensive smart bomb to blow up a guy camping in a foxhole with an RPG-7 waiting for Marine hovercrafts or would you just drop a big shell on him?

Also the only cruise missiles that will pierce a BBs armor are the new Russian supermissiles like the "Granit" and Russia is not selling those to anyone yet. Battleship armor is practically impervious to crappy subsonic (aka exocet type) missiles that rogue nations or China could get their hands on.