American intelligence believes that China is equipping some of its DF-15 missiles with GPS guidance and aiming them at U.S. bases in Okinawa. There are several brigades of American marines based in Okinawa, plus dozens of American combat aircraft. But this requires moving DF-15s farther up the coast, away from Taiwan. The DF-15s only have a range of 600 kilometers and Taiwan is 640 kilometers from Okinawa. So the DF-15s currently aimed at Taiwan would have to move to bring Okinawa into range. However, these missiles could still hit Taiwanese targets.