Sorry, but the Iowa class is completly outdated and its 16"-guns are too expensive and (compared to the price to maintain such heavy equipment) ineffective. They were "top of the line" in 1939 when they have been introduced. Today they are simply scrap. Maybe you remember the shelling (after the Marines left the country due to their heavy losses in a terror act of the Hezzies) of northern Lebanon in 1984 that ended in some impressive fireworks but with no measurable effect (I think a few people including a Syrian commander died, but nothing really decisive).
The US navy would be much better off if they buy modern German naval technology if they are interested in the capability of traditional shelling of hostile land with ships:
Modular Naval Artillery Concept (MONARC) was a study of the German defence industry about mounting the turret of the PzH 2000 self-propelled howitzer on a naval ship of frigate size.
The size required above and below deck and the weight of this turret are not much different to the OTO Melara 76mm gun system, the standard naval gun of the German Navy. But to deal with the much greater recoil of the 155 mm artillery piece on such a small vessel, a flexible mount with damping elements had to be designed.
This mount and a PzH 2000's turret was fitted experimentally in December 2002 on the Type 124 Sachsen class frigate Hamburg at the shipyards of HDW in Kiel, when she was still fitting out. 2004 the fire-control system was tested with a PzH 2000 strapped onto the helicopter deck of Hessen, another Type 124 frigate. The feasibilty of using even the unmodified PzH 2000 with unguided "dumb" rounds to attack naval targets had been proven previously by the Swedish Coastal Artillery with tests performed in May 1996.
Rheinmetall, the producer of PzH 2000's gun system, plans to design special smart naval rounds that will boost the range of the gun from 30km with standard NATO ammunition and 40km with assisted rounds to over 80km, more than many anti-ship missiles.
The future F125 class frigate will very likely make use of this concept.
155 mm/52 MONARC on German Frigate FGS Hamburg
155 mm/52 MONARC prototype at Rheinmetall proving range in Unterlüß in June 2003 Note the elaborate "Flexible Mounting" required
The Panzerhaubitze 2000, or PzH 2000 for short, is a 155mm self-propelled howitzer developed by Krauss-Maffei Wegmann (KMW) together with Rheinmetall for the German Army. It is arguably the most powerful artillery system currently deployed. It is particularly notable for a very high rate of fire; in burst mode it can fire three rounds in 9 seconds, ten rounds in 56 seconds, and can fire between 10 and 13 rounds per minute continuously depending on barrel heating. PzH 2000 has also been selected by the Italian, Dutch and Greek Armies, and more orders are highly likely as forces upgrade their outdated M109 Paladins.
The loading of shells is automated, two operators should be able to load 60 shells in 12 minutes.
In April 2006 a PzH 2000 shot assisted shells (Denel V-Lap) over a distance of 56km with a probable maximum range of over 60km
Although the caliber is smaller it is possible to provide equal much (or effectivly even more) firepower that is much more accurate with 3 small and cheap frigates. If the MONARAC turrets are deployed on a larger ship than a frigate you have a very effective possibility to bombard cheaply hostile territory.