Last week the Taipei Times, ran an article quoting Chinese Gen. Chen Bingde confirming the existence of the DF-21D, this would be the first time a Chinese official confirmed it's existence.
Further down in the article Chen Bingde stated that the DF-21D has a range of of 2,700km, which is is almost twice as much as the estimate of 1,500km given by the Navy. Chen Bingde also stated that the DF-21D is still in the development stage and that such high-tech devices were difficult to bring to bring to maturity. Earlier this year the company which produces the DF-21D claimed that it would field a 4,000km IRBM (Intermediate Range Ballistic Missile), along with that Chen Bingde stated that a 2,700km range is easy for them.
However, I am skeptical about a 2,700km range for the DF-21D because the Chinese have had problems with high-tech equipment (aircraft engines for example), and the fact that MARVs are not simple things to produce and are very complicated. On top of this the Chinese will be depending on a series of satellites to to feed information to the DF-21D, and satellites can be damaged by flashing lasers at them. Back during the Cold War the Soviets flashed lasers at the Space Shuttle, which caused some problems on the shuttle and discomfort for the crew.
Overall, the DF-21D is an interesting question, but there still are many kinks to work out in the DF-21D, but, given time the DF-21D could mature into a threat.
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