April 6, 2007: The U.S. is building a support base, at the Indian Ocean island of Diego Garcia, for the SSGN (an SSBN converted to carry 154 cruise missiles, and a hundred or more SEAL commandos) that has joined the Pacific fleet. SSGNs, like the SSBNs, have two crews, so that the boats can be kept at sea for the maximum amount of time (every 90 days, the SSGN comes into port to change crews). Commandos can also be carried aboard the SSNs, but the SSGN boats have additional facilities for the SEALs to plan, exercise, and train for missions. Few details of what the support base will contain, but it will obviously enable the SSGN to hang out for longer periods in the Indian Ocean, on an island due south of the Persian Gulf, and Iran.