The U.S. Navy believes that the long rumored Chinese anti-ship ballistic missile, the DF-21D, is operational. This despite the fact that, as far as anyone knows, or will admit, the complete system has not been tested. There are hints that there were some tests last Summer, and that all the components of the system are present and working. There are photos of DF-21Ds on TELs (transporter erector launcher vehicles), and announcements of new units recently activated for the 2nd Artillery Missile Brigade, equipped with DF-21 missiles. Since all that took place a few months ago, Chinese officials have spoken about not being as concerned about American aircraft carriers. But the key event occurred last August.
Back then, China launched another "remote sensing" satellite, joining two others in a similar orbit. These three birds are moving in formation, at an altitude of 600 kilometers, across the Pacific. Equipped with either radar (SAR, or synthetic aperture radar) or digital cameras, these three birds can scan the ocean for ships, even though the Chinese say their purpose is purely scientific. A typical SAR can produce photo quality images at different resolutions. At medium resolution (3 meters) the radar covers an area 40x40 kilometers. Low resolution (20 meters) covers 100x100 kilometers. This three satellite Chinese posse looks suspiciously like a military ocean surveillance system. This is the missing link for the rumored Chinese ballistic missile system for attacking American aircraft carriers.
For nearly five years, there have been stories (in the West) about how China was working on targeting systems for its ballistic missiles, that would enable them to seek out and hit aircraft carriers. Such sensors would use infrared (heat seeking) technology for their final approach. This sort of thing had been discussed for decades, but China appeared (according to pundits and headline hungry media) to be putting together tactics, and missile systems, that could make this work. The key was having multiple sensor systems, either satellites, submarines or maritime patrol aircraft, that could find the general location of the carrier, before launching the ballistic missile (like a DF-21, with a range of 1,700 kilometers). Those sensors appear to be operational, as do the other elements needed to make the DF-21D work.