China has recently announced the finalization of a new missile, the Dong-Feng 21D. The DF 21 series has shown itself capable and adaptable up to this point, the other variants being able to target everything from land bases to satellites.
The United States' carrier force is the base unit of its power projection, not just in the pacific, but around the world. A third of the active cruisers and destroyers in the fleet are designed for the sole purpose of protecting the carrier group once it is at sea.
The new DF-21D throws this strategy into doubt. The missile deploys in stages. First, it boosts up into the upper atmosphere and then comes screaming back down. About five hundred meters before it hits the surface of the ocean, it levels off sharply and cruises along to its target, hence the classification "Waveskimmer".
The missile is already allegedly difficult to track, add to that the fact that the waves create confusing radar echos and the missile is traveling at well over Mach five, it is easy to see why the Pentagon is abuzz at the moment.
The DoD claims they are researching countermeasures, and the citizens of the United States had better hope so, because as previously mentioned, the carrier group is the cornerstone reason that America continues to dominate the world stage. It is important to note that even if counter measures are developed, if China can produce the missile in large enough quantities it can overwhelm any system with a swarm attack, no matter how accurate.
The current missile defense systems of the US fleet are mainly the aforementioned cruisers and destroyers which have their Anti-Ballistic Missiles slaved to a fleet-wide targeting system, allowing for universal decisions on the fly.
China has displayed its buying power, and has demonstrated the ability to guide the missile from land stations, radar carrying aircraft, and the brand new Chinese satellite system. It is possible that a US counter strategy would be to shoot said satellites down.
In conclusion, the mere existence of these new weapons poses a dire threat to US power projection abroad. China has shown no compunction about selling weapons to enemy regimes such as Iran and North Korea, so it is possible that fleet High Command could wake up one day to find that the only safe place for their ships is US harbors.
This shift of power has implications for every scenario in the far east including operations in Korea should that hot spot boil over, operations in and near Taiwan should China choose to re-take the land, and for the many US soldiers stationed in Asian bases and ports of call who may find themselves stranded if war breaks out.