The US Navy has begun development of a new ship, currently designated 'DDX.'  In addition to the standard missions of a surface warship (air defense, anti submarine and anti ship warfare) the DDX will be designed to provide support for Marine amphibious landings.  It will achieve this with a combination of missiles and a pair of 155 mm guns.
 
As is the case with virtually every other new development program, costs have started rising and the sticker shock has begun generating questions about alternatives.  Each of the new DDX vessels is currently expected to cost $1.7 billion, but that is surely lower than the ultimate price. For a fleet of DDXs, the total cost will be substantial, even on the scale of federal budgeting.

One of the alternatives being advocated in some quarters is reactivating two of the old Iowa class battleships. These old ships from World War II are truly incredible machines, armored with steel up to 17 inches thick and armed with nine 16 inch (406mm) guns and twelve 5 inch (127mm) guns.  By any measure these are impressive machines.
 
But there is one big problem with them, one which makes the seemingly thrifty decision to recycle them a bad choice. They're antiques!  Meaning that reactivated battleships are going to have problems and extra costs that no amount of modernization can possibly fix.
 
Manning.  A modern warship has a significant amount of automation.  The old battleship required over 1500 sailors, a modern destroyer requires less then 400 men, and the DDX will need less then 100.  In addition, the sailors for the battleship will have to be trained to operate equipment that's unique to the ship they're serving on.  This will make it difficult to transfer sailors from a battleship to any other ship. 

Assigned to a battleship? I hope you like it, because you'll be spending your whole career there.   It should also be pointed out that personnel represent one of the largest significant long term costs for any warship.  That's why the Navy is spending billions on new automated ship systems.
 
Maintenance.  Ever try to find parts for a 20 year clunker that happens to be your sole source of transportation?  Same thing applies here. True some parts can be scavenged from museum ships, but replacements for parts that wear out quickly are gone now, and will have to made from scratch.  This is intensely expensive.  And then there's the consumables, like gaskets, seals, hydraulic fluid and a hundred other piddly little items that were standard back in the forties and fifties, but are only a memory now.
 
Technology.  Yes, the DDX is expensive. That's because this program is being used to develop a range of new systems in propulsion, protection, power generation and stealth, that will be applied to a brand—new generation of naval warships.  

One example is the 155 mm gun with which the DDX is going to be armed.  This gun will be completed unmanned, and will be capable of firing the same shells that the army's 155 mm artillery guns use.  A shell presently in development will have a range of over 100 miles and will be GPS guided.  You don't need a battleship's 2 ton shell, when you can hit a postage stamp at 100 miles.
 
Protection.  Much has been made of the superior armor protection of the battleship.  Up to 17 inches of steel plate protect the vitals of these mighty machines. But even better armor didn't save the Bismarck, the Yamato, or any number of other battleships that were in the wrong place at the wrong time.  The principle protection of any warship in any time is an alert crew and the other ships of her task group.  Lots of steel armor helps, but in the final analysis a well—placed shot can cripple and/or impair anything.  A modern torpedo is designed to detonate under its target.  This is a devastating attack and will sink pretty much any ship ever made, including a battleship.
 
Numbers.  Any ship—to—ship comparison of the firepower between one of the battleships and the DDX favors the battleship.  Except that there are only 4 battleships.  The current DDX program envisions between 8 and 12 ships.  It could be argued that the program will be cut back, that fewer ships will be built. But the same could be said for any reactivation of the battleships.  If, on the other hand more ships are needed, additional DDX's could be built.  Almost any other limitation of the battleships could be overcome if there were enough money spent on their modernization, but not the lack of ships top renovate.  There can only be four revitalized battleships, no matter how badly you might need more.
 
That last argument touches the deepest roots with my discontent at reactivating the battleships at the expense of the DDX program.  The battleships represent the past, and no matter what you do with them, they'll remain limited by that past.  The DDX is the future, and the technology developed for it will make every ship built after it more effective and devastating to our enemies.
 
In 1980 I was assigned to the number one main machinery room of the aircraft carrier USS Ranger.  She was launched in 1958, a year before I was born.  Thus, I have first hand experience at keeping old and obsolescent equipment running. We did it with long hours, sweat and occasionally blood, (6 shipmates of mine died in the engineering spaces during my tour of duty).  It was not a pleasant experience.  I would spare another generation of sailors that pain.  The old battleships are museums pieces now, and that is the best way they can serve their country.