Trump's 'Golden Dome' missile defense system could cost $1.2 trillion, far above initial estimate

US President Donald Trump's "Golden Dome" missile defense network is projected to cost far more than initial estimates, according to an analysis released Tuesday by the Congressional Budget Office (CBO).

The agency is pegging the cost of the system's development, deployment and sustainment over a 20-year period at roughly $1.2 trillion. That is several magnitudes higher than the $175 billion price tag Trump put forward last year shortly after he assumed office.

The vast majority of the costs -- over $1 trillion -- are attributed to acquisition, including multiple layers of interceptors, space-based early-warning and tracking systems, and research and development, the CBO said.

The non-partisan report found that space-based interceptors would account for roughly 70% of total acquisition costs, and 60% of costs overall.

Only about $24.4 billion has been approved by Congress for the program so far.

The system is intended to fully cover the US, including Alaska and Hawaii, and Trump said in his Jan. 27, 2025 executive order that "the threat of attack by ballistic, hypersonic, and cruise missiles, and other advanced aerial attacks, remains the most catastrophic threat facing the United States."

"Over the past 40 years, rather than lessening, the threat from next-generation strategic weapons has become more intense and complex with the development by peer and near-peer adversaries of next-generation delivery systems and their own homeland integrated air and missile defense capabilities," he said.

The CBO acknowledged that its estimate is complicated by a lack of details on the program's size and scope from the Pentagon making "it impossible to estimate the long-term cost of the GDA system being contemplated by DoD." The office was using an acronym to refer to the "Golden Dome for America," another name for the program.

"In the absence of specific plans for GDA’s objective architecture, CBO has estimated the cost of a notional NMD architecture based on the defensive systems and capabilities that are called for in the executive order," it said, referring to the national missile defense system.