Congressional Budget Office estimates Trump’s Golden Dome missile defense plan would cost about $1.2 trillion over 20 years

Why is the estimate described as uncertain?

The CBO said it was modeling one illustrative version of a system with capabilities broadly consistent with Trump’s executive order, not pricing a finalized administration design. It said the lack of detailed Pentagon or White House specifications made long-term cost estimates for the actual system difficult Hindu,CBC News,Bloomberg Business.

What parts of Golden Dome drive most of the cost?

The largest expense is the planned space-based interceptor layer, alongside a space-based missile warning and tracking system. The CBO said acquisition costs would exceed $1 trillion, and that the space-based interceptor portion would make up about 70% of acquisition costs and about 60% of total costs NDTV,Reuters,NYT.

Would the system guarantee protection against missile attacks?

No. According to the CBO analysis cited by multiple outlets, even a fully built system could be overwhelmed by a large-scale attack from a peer or near-peer adversary such as Russia or China, meaning the plan’s effectiveness against the most demanding scenarios remains in question NYT,infobae,Bloomberg Business.