A new Congressional Budget Office (CBO) estimate says President Donald Trump’s proposed “Golden Dome” missile defense system could cost about $1.2 trillion over the next 20 years to develop, deploy, and operate. Multiple outlets report that the CBO frames the figure as an estimate because the Department of Defense has not released enough details about the envisioned system architecture, making a “true” cost difficult to determine. The estimate includes more than $1 trillion in acquisition costs for a national missile defense system, with a substantial portion tied to developing and deploying space-based missile interceptors, which do not currently exist. One report says space-based interceptors likely account for about 60% of the total cost, reflecting the major upfront investment required. Another outlet reports that CBO projects average annual operations and support costs of about $8.3 billion. Separately, Trump administration officials involved in the program dispute the CBO’s estimate, saying it relies too heavily on past missile-defense performance and does not fully account for expected technological advances. The report and ensuing debate focus on the scale of deployment and the costs of high-end interceptors planned for the system.