Or so I've read somewhere. I have a link for an article, but not the one I want.

Japan Silent After Taiwan Anti-missile Remarks

In the report linked to above, America and Japan are sharing anti-missile technology in order to hasten development of the US Navy's SM-3 missile that is intended to destroy enemy missiles at high altitudes. The Theater Missile Defense agreement was signed with North Korea's emerging missile capabilities in mind. Taiwan apparently wants in on the program. China, of course, doesn't want Taiwan included.

And now I think we know the real source of China's opposition to NMD. China possesses around the same number of nuclear missiles as NMD claims it could neutralize. Perhaps even more important - since a Chinese nuclear attack against America would be suicide for Beijing - are China's concerns about Taiwan. That seems to be the real fear, that missile defense would be extended to Taiwan, rendering the threat of Chinese missiles useless.

China Rebuffs U.S. on Missile Shield

'In addition to the National Missile Defense (NMD) scheme, Bush is also considering a Theater Missile Defense (TMD) to protect allies such as Japan or U.S. troops in northeast Asia.

China is strongly opposed to both, fearing NMD would negate the effectiveness of its small nuclear force and TMD would cover Taiwan and thwart Beijing's efforts to recover the island it claims as a renegade province.

"We more strongly oppose calls by some people to involve Taiwan in TMD, which would violate China's sovereignty," he said.'

China's schemes to annex Taiwan meet yet another roadblock if Taiwan can shoot down Chinese missiles.

NMD remains useless against terrorist attacks. Instead of being pursued all at once, my opinion is that it should be pursued a piece at a time. The TMD is far more doable than NMD, and will provide a proving-ground for some components of a future NMD.

Continue the R&D, by all means, but avoid any foolish and headlong rush to deploy an unready system. The fact NMD makes China so uncomfortable remains the strongest argument I've heard for pursuing NMD. That does not change my opinion that NMD is not yet ready for deployment. Since NMD is destabilizing and will set off a renewed arms race - likely accompanied by a renewed Cold War - it should only be deployed when it can actually be shown to work.

In my opinion.