The LCS (Littoral Combat Ship) is seen as the model for the 21st century navy. While the aircraft carrier will remain the capital ship, the next generation of them (the CVN 21 class) will be very different from current carriers. The navy wants to spend more money, and effort, on increasing the capabilities of sailors, using more robotics and making the navy more mobile and in touch. Admirals recognize that, unlike in the past, there is no one enemy fleet you go after. The future threats will be all over the place, and you have to be able to get to them quickly, and with the kind of forces that will take care of the problem before it gets any worse. The navy is looking at doing more with mobility, in the same sense that the army has long studied that issue.
All of this means more jointness (close cooperation with the other services.) Up until the 1991 Gulf War, the U.S. Navy was, as it had long been, a force unto itself. But after several embarrassing moments during the Gulf War (difficulty in communicating with the other services, lack of the right weapons and some cooperation problems), the navy turned around. Since then, the navy has provided one carrier to the army, to transport an infantry division to Haiti, and another to serve as an offshore base for SOCOM helicopters in 2001. Naval aviation was crucial in the 2001 Afghan invasion, and now the navy wants to institutionalize this kind of cooperation. For centuries, admirals operated far from home, and communication took so long that the sailors had to act on their own. But the world is a much smaller place now, especially when it comes to communications. Soldiers can get to distant battlefields, via air force transports, long before the navy amphibious ships can. So the navy wants a force that can communicate faster, see more and act more quickly than ever before.
This means a very new type of navy, one that it is having a hard time selling to Congress, and the many influential supporters of the traditional, "high seas," navy. The politicians have come to rely on those very expensive contracts for building large warships. But the navy is pulling back from that, and getting some political heat as a result. Its tough to sell the politicians on a lot of untried ideas. But its a new century, with new technology. If the U.S. Navy doesnt figure out what to do with all this, someone else may.
The U.S. Navy is working on a dramatic change in weapons, ships and tactics. Many admirals believe the navy has been resting on its laurels, brought about because of the lack of any real opponents since World War II. The Soviet Union tried to provide a meaningful threat, but, when you consider Russian naval history, the smart money was always on the U.S. fleet. The navy could continue to dominate the oceans using the World War II model, but there are better ways to do it today, and thats what is driving the current changes.