The report, Build Your Own Golden Dome: A Framework for Understanding Costs, Choices and Tradeoffs, was authored by AEI senior fellow Todd Harrison. He calculated costs by collecting estimates for interceptors, aircraft, communications platforms, radars and counter-drone systems, before modelling six example architectures.
“Its cost hinges on the level of geographic coverage, the types and numbers of threats it must address and the degree of resilience it is expected to achieve,” the report said. It added that even small adjustments in these factors could alter the price “by hundreds of billions of dollars.”
The most expensive example costed $3.6 trillion over 20 years in fiscal year 2026 dollars, while the least was roughly $252 billion. These sums represent “additional funding required beyond the current baseline,” meaning “if something is already funded in the baseline, this funding is not included in the total cost shown for each architecture,” the report stated.
Golden Dome received an initial $25 billion via the One Big Beautiful Bill Act signed in July. More funding is expected through the president’s fiscal year 2026 budget and subsequent allocations.
However, the report noted that “as long as these requirements remain undefined, it is fair to say that Golden Dome can cost as much or as little as policymakers are willing to spend.” It also highlighted President Trump’s announcement, saying: “In his Oval Office announcement, President Trump set a high bar for Golden Dome, declaring that it would complete ‘the job that President Reagan started 40 years ago, forever ending the missile threat to the American homeland and the success rate is very close to 100 percent.’”
Harrison’s least costly projection described a “limited tactical defence” aimed at countering drone swarms, aircraft and cruise missiles using layered defences to protect key sites. The most expensive scenario sought maximum protection across all threat types “with the sole constraint that annual costs not exceed 25 percent of the current defence budget.”
Even with this higher target, the report found it “can only afford the robust capacity level for one of the three types of [space-based interceptors] considered.” It added that all five of the less ambitious architectures also showed significant gaps.
By contrast, the report said Trump’s $175 billion proposal would deliver “a system that is no match for the quantity of missiles China and Russia possess,” producing a result “far short of what the president promised, creating a multi-trillion-dollar gap between rhetoric and reality.”
The report concluded that “in the end, Golden Dome’s cost will not be determined by fiscal constraints or technical capabilities, but by political choices: which risks leaders are willing to mitigate, which they are willing to trade and which they are prepared to accept.”
Read the full report here.
