Barring significant internal strife, an economic collapse or a major war, China's navy will continue its significant rise in the decades to come and continue to close the gap on its U.S. counterpart.
By 2030, the Chinese will likely be the dominant naval force in a line stretching up to the Philippines, and will have a further zone of advantage out into the Pacific Ocean.
The U.S. Navy, on the other hand, will largely remain paramount on the rest of the world's oceans and seas.[emphasis added]
So yes, as Straftor notes:
The coming decade of development will significantly reduce, but not eliminate, the gap between China's navy — already the second most powerful maritime force on the planet — and the U.S. Navy by 2030.
What we will see, I think, barring events that interrupt that Chinese navy rise, is a more pronounced shift of American naval power to be within range of the western Pacific--from the Indian Ocean to the west coast of America.
Once the Cold War ended, America began to shift forces away from Europe, with "the pivot" formalizing the shift and looking to divide our fleet 60-40 weighted to the Pacific up from 50-50 in the Cold War. Our once-massive Mediterranean fleet pretty much evaporated. For a time (until recently) we didn't even have an Atlantic fleet.
And once China's fleet becomes even more powerful, the shift will become more pronounced, in the manner that Britain concentrated their global fleet in home waters as the German fleet rose in power in Europe:
[British] Admiral John Fisher, who became the First Sea Lord and head of the Admiralty in 1904, introduced sweeping reforms in large part to counter the growing threat posed by the expanding German fleet. Training programs were modernized, old and obsolete vessels were discarded, and the scattered squadrons of battleships were consolidated into four main fleets, three of which were based in Europe. Britain also made a series of diplomatic arrangements, including an alliance with Japan that allowed a greater concentration of British battleships in the North Sea.To concentrate power in or near the Pacific, America would need to leave securing the Atlantic and Mediterranean Sea largely to our NATO allies (including Canada) who have significant if dispersed naval power to block Russia's weak navy from Norway to the Mediterranean Sea.
America would have to shift Fifth Fleet from the Arabian Sea center of gravity to the the east from Diego Garcia to Darwin and Perth (where they'd still be able to respond to Central Command problems), to support operations against forces in the South China Sea from the Indian Ocean, with logistics and military support from Australia.
Putting American assets on the eastern end of the Indian Ocean also helps keep our fleet within supporting distance of Pacific assets. And with more Chinese warships heading for the Indian Ocean, an American naval force based out of Australia will be able to hammer the Chinese ships, bolstered by American and allied land-based air power in the Gulf region and Diego Garcia (plus the Indian navy).
America's regional allies would step up their abilities to secure sea lines of communication in the Persian Gulf region (like Saudi Arabia), with larger ships that even now are being built for Qatar (which I noted here) in the region. Britain will help there, too. Don't forget that America could expand the deployment of smaller vessels in the Gulf backed by air power there. And diverting some of the oil traffic away from the Strait of Hormuz is one element of that protection.
And as far as I'm concerned, I don't know why land-based air power can't replace carriers in the Middle East (and in the Mediterranean Sea and North Atlantic, for that matter--with land-based planes in Norway, Britain, and Iceland defending the Greenland-Iceland-UK gap to secure trans-Atlantic lines of supply).
Don't forget that in Asia, America may have the support of powerful Japanese, South Korean, Indian, and Australian navies and air forces; plus smaller forces from allies and friends like Taiwan, the Philippines (where bases would be more important), Vietnam, Thailand, Indonesia, Singapore, and New Zealand.
And America will need to integrate land-based air power from the Air Force into the naval effort in the Pacific.
China's fleet rise will not take place in a static environment. It is worrisome, no doubt. But America will do things other than build more ships and train our crews more diligently.
And optimistically, if China only wants a fleet to protect their sea lines of trade that America has no interest in cutting outside of a war that we don't want, China's stronger fleet will be no threat anyway.
UPDATE: This terminology change reflects my view that rising Chinese naval power will compel America to concentrate naval power in or near the Pacific--including the eastern Indian Ocean:
The Pentagon may soon be announcing a new name for its largest area of operations, with a change to Indo-Pacific Command to “better encapsulate the responsibilities the command currently has,” Pentagon spokesman Army Col. Rob Manning said Monday.
INPACOM?
UPDATE: I was really hoping for PAINCOM.
