The Pentagon has given defence companies their clearest look yet at “Golden Dome,” the national missile shield championed by President Donald Trump. Slides obtained by Reuters and shown last week to about 3,000 contractors at the Space and Missile Defense Symposium in Huntsville, Alabama, outline an ambitious, four-layer architecture designed to protect the United States from a range of airborne threats. According to the presentation, the system would start with a space-based layer of satellites for missile warning, tracking and potential boost-phase interception. Three ground-based layers—built around radars, interceptor missiles and possibly lasers—would follow. Plans call for 11 short-range interceptor batteries spread across the continental United States, Alaska and Hawaii, and a new missile field in the Midwest equipped with Next Generation Interceptors. The Pentagon estimates Golden Dome will cost about $175 billion and enter service in 2028. Congress has already appropriated $25 billion, and the administration is seeking another $45.3 billion in its 2026 budget request, but officials say the exact numbers of launchers, interceptors and ground stations are still being determined. Space Force General Michael Guetlein, appointed programme lead in July, must deliver an initial system design within 60 days and a full implementation roadmap within 120 days. Defence giants Lockheed Martin, Northrop Grumman, RTX and Boeing are expected to compete for contracts, while Elon Musk’s SpaceX—once considered a contender—was notably absent from the latest planning documents.