Book excerpt: As part of its effort to develop a global ballistic missile defense (BMD) system, the Department of Defense (DOD) has modified three Navy cruisers and 15 Navy destroyers for BMD operations, and has deployed a large BMD radar - the Sea-Based X-Band Radar (SBX) - on a modified floating oil platform. In August 2008 it was reported that the Navy has decided to increase the number of BMD-capable destroyers from 15 to at least 62. The eventual role of sea-based systems in the worldwide U.S. BMD architecture has not been determined. The overall issue for Congress discussed in this report is: What should be the role of sea-based systems in U.S. ballistic missile defense, and are DOD ssssssss programs for sea-based BMD capabilities appropriately structured and funded?