Trump's Golden Dome Missile Defense to Cost $1.2 Trillion Over 20 Years, CBO Estimates

President Donald Trump's proposed Golden Dome missile defense system will cost about $1.2 trillion ($882 billion) to develop, deploy and operate over two decades, according to a new report from the nonpartisan Congressional Budget Office.

The estimate exceeds the initial $175 billion ($129.25 billion) figure by a wide margin. Acquisition costs alone would surpass $1 trillion, covering interceptor layers and a space-based missile warning and tracking system, the report stated Tuesday.

The Golden Dome seeks to protect the entire United States from aerial threats, including ballistic and cruise missiles. Trump unveiled the plans shortly after returning to the White House in January, targeting next-generation aerial threats.

He said last year the program would need an initial $25 billion investment, with a total of $175 billion over time.

Democratic Senator Jeff Merkley, who requested the CBO estimate, said Tuesday: "The President's so-called 'Golden Dome' is nothing more than a massive giveaway to defense contractors paid for entirely by working Americans."

Experts question whether the U.S. can build a comprehensive defense over such a vast land mass. Officials note that current systems lag behind sophisticated weapons held by potential adversaries.

The CBO report warned the system could be overwhelmed by a full-scale attack from Russia or China. An executive order for what was first called the "Iron Dome for America" stated that next-generation weapon threats have grown more intense and complex, posing a potentially catastrophic risk to the U.S.

A week into his second term, Trump directed the Defense Department to develop plans for a system to deter and defend against aerial attacks. The White House called such attacks the most catastrophic threat facing the country.