US Intelligence agencies believe that China is building a missile carrying submarine (the Type 094) that will carry a smaller version of their new DF-31 ICBM. Using US W-88 warhead technology, the smaller missile will have a range of 7,400 miles, this allowing the Type 094 subs to hide out in the Pacific while threatening the entire United States with nuclear destruction. The first Type 094 is not expected to be ready for service until 2006. American submarine technology is far superior to anything the Chinese have, or will have, in the near future, so the Type 094, as with the former Soviet Unions missile subs, will be tracked by US attack subs. But the American boats cannot attack until the Chinese launch, or announce they are going to do so (you can't always depend on that.)