President Donald Trump wants to build a missile defense system that stretches from the ground to outer space. The Pentagon’s price tag: $185 billion through 2035. The Congressional Budget Office’s price tag: roughly $1.2 trillion over two decades. That’s not a rounding error, it’s a sixfold gap that tells you everything about how contested this program already is.
The initiative, dubbed the “Golden Dome” after an earlier working title of “Iron Dome for America,” aims to defend the US homeland against ballistic missiles, hypersonic missiles, and other aerial threats using a layered architecture spanning ground, sea, air, and space.
What the Golden Dome actually involves
Trump first issued an executive order on missile defense in January 2025, then formally announced the Golden Dome initiative in May 2025. The program is led by US Space Force Gen. Michael Guetlein and represents the most ambitious missile defense concept since Ronald Reagan’s Strategic Defense Initiative in the 1980s, the program critics nicknamed “Star Wars.”
The core idea is to merge existing, proven systems like the Patriot and THAAD missile defense batteries with a new constellation of space-based interceptors and tracking satellites. The space layer is the expensive part. The CBO estimates that space-based interceptors alone would account for roughly 60% of the projected $1.2 trillion total cost, driven by the need for thousands of satellites in orbit capable of detecting and destroying missiles during their boost phase.
