President Trump’s plan for a “Golden Dome” missile defense system to cover the entire territory of the United States would cost $1.2 trillion to build and operate, according to a Congressional Budget Office (CBO) assessment, dramatically more than the White House has requested for the project.
Defense One noted that the $1.2 trillion figure is seven times larger than President Trump’s original promise to build it for $175 billion and 15 times more than the $79 billion the administration plans to spend in the Golden Dome for America account over the next five years.
The CBO based its assessment on the objectives of the “Iron Dome for America” Executive Order that President Trump signed back in January 2025. At the time, he was comparing the potential system to Israel’s Iron Dome, but the Israeli system is designed for intercepting crude, short-range rockets over a vastly smaller country, and Trump’s vision would be to provide a protective shield to defend from advanced ballistic missile attacks.
The CBO said that creating such a system would require four layers: a space-based layer, two wide-area surface layers (an upper and a lower layer), and a surface-based regional sector layer. It said that the space-based layer would be by far the most expensive, accounting for 70% of acquisition costs and 60% of total expenses.
The CBO’s estimate includes over $1 trillion in acquisition costs plus operations and maintenance costs over 20 years, but experts say the real number for building what Trump has described would be much higher.
“CBO assumes the deployment of fewer than 7,800 space-based interceptors [for Golden Dome]. But the ratio of space-based interceptors to missiles fired necessary to cover the entire United States could be as high as 1000 to 1,” Gabe Murphy, a policy analyst at Taxpayers for Common Sense, told Responsible Statecraft.
Todd Harrison, a defense analyst and space expert with the American Enterprise Institute, said in a report last year that building a system most closely to what President Trump has described would cost $3.6 trillion over 20 years. He told Defense One that the fact that the CBO’s estimate is so much higher than what the White House has requested for the project means the “administration is not actually building what the executive order described.”
