CBO Estimates Golden Dome Missile Shield Could Cost $1.2 Trillion Over 20 Years

Analysis
The structural incompatibility between the executive order's space-based interceptor mandate and orbital physics, not acquisition strategy or launch economics, produces the cost gap. Roughly 7,800 interceptors are needed for just ten simultaneous ICBM intercepts because LEO satellites cannot hover over fixed threat regions. Atmospheric drag at 300 to 500 kilometers forces full constellation replacement roughly every five years, compounding to approximately 30,000 satellites over two decades regardless of how efficiently they are manufactured or launched. Guetlein publicly conditioned SBI production on affordability thresholds in congressional testimony, signaling that DoD leadership has already internalized the scalability ceiling the executive order cannot override. Space-based interceptors are likely to remain confined to prototype development rather than operational deployment through the current Future Years Defense Program window ending in 2031, because the $185 billion ceiling cannot support an operational constellation at any militarily relevant scale. The tracking satellite layer represents the more durable investment case, as CBO finds sensors necessary regardless of which final architecture DoD selects. The more immediate oversight risk is the transparency gap: without a public DoD architecture, Congress is authorizing and appropriating for a program whose actual scope and cost cannot be independently bounded.