Missile Defense at Any Cost?

Assessing the Feasibility and Consequences of the Golden Dome Missile Defense Project

Picture: White House

This week, U.S. President Donald Trump outlined his plans for the United States’ “Golden Dome” missile defense project. The name is modeled after Israel’s “Iron Dome” missile defense system, which protects Israeli territory against short-range rockets and projectiles, including mortar and artillery rounds.

In contrast to Iron Dome, however, the President Trump’s demands for the program are much more ambitious, aiming to defend the continental United States from a divdrse range of missile threats, including hypersonic missile systems, cruise missiles, and nuclear-armed ballistic missiles.

According to the plan, the U.S. Congress is being asked to provide an initial “down payment” of $25 billion, followed by an additional $175 billion over the next three years. Trump stated that the project would be completed within his current term and claimed it would protect the U.S. homeland with a success rate “very close to 100 percent.”

This post analyzes the Golden Dome project, including its technical feasibility, economic rationale, and potential political ramifications. In short, if Golden Dome focuses on defending the United States against cruise missiles, short- and medium-range ballistic missiles, and long-range drones, it stands a good chance of meaningfully contributing to U.S. defense and deterrence, potentially even within a relatively short timeframe. However, if the focus shifts toward deploying a space-based strategic missile defense system, as strongly implied by Trump in recent media appearances, the costs are likely to outweigh the benefits.

A cost issue

The basic outline of Trump’s missile defense plans was provided in Executive Order 14186 on 27 January 2025, which instructed to Secretary of Defense to submit, within 60 days, a plan for a next-generation missile defense system, covering protection against ballistic, hypersonic, advanced cruise missiles, and other aerial threats. Priorities include accelerating space-based missile defense capabilities, establishing underlayer and terminal-phase defenses, and integrating non-kinetic systems.

By far the most ambitious component of Golden Dome is its planned space-based interceptor capability. The concept itself is not new. Space-based missile defense was first pursued by the Reagan administration nearly 40 years ago, but the effort was ultimately abandoned, primarily due to major technical challenges and its prohibitive costs.

Since the Cold War, and especially over the past decade, missile defense technologies have advanced greatly, as current developments in Ukraine demonstrate. Nevertheless, the scope envisioned by Trump, along with the projected costs, is almost certainly unrealistic and unlikely to be realized within the proposed timeframe.

For one thing, several of the missile defense capabilities outlined by Trump, most notably space-based interceptors, do not currently exist in the U.S. arsenal and would need to be developed from scratch. While the United States can likely leverage existing technologies to speed up the process, validating system designs, building prototypes, and deploying fully operational assets, including into space, will take years, if not decades.

Cost will also be a major hurdle. An independent study by the Congressional Budget Office estimated that deploying an effective space-based interceptor system capable of reliably defending against a limited North Korean nuclear missile threat would cost between $160 and $540 billion over 20 years. A system designed to defend against the much larger arsenals of China and Russia would cost several times more, likely resulting in a multi-trillion-dollar price tag (in any case significantly more than the $200 billion Congress is asked to allocate), and would almost certainly not provide the 100 percent success rate envisioned by Trump.

While the costs of launching military systems into space has decreased drastically since the Cold War — not least thanks to the entrance of private space industrial actors that offer low-cost orbital launches, including to government actors —, interceptor and support system costs remain high.

Conservative estimates suggest that each space-based interceptor could cost between $100 million and $300 million over its lifecycle. Since these interceptors would need to maintain persistent orbital coverage, ensuring the ability to engage missile targets during the boost phase at specific geographic locations on short notice would likely require a constellation numbering in the thousands.

The United States would also need to drastically expand its space-based surveillance and early warning capabilities to support such a system. This would likely entail additional tens of billions in funding for satellites capable of detecting and tracking inbound missile threats and cueing interceptors.

Countervailing effects

Beyond questions of cost and feasibility, political concerns remain.

Even if the United States were to bear the immense expense of deploying a space-based missile defense system that is at least nominally capable of countering peer adversary nuclear threats, there is little reason to believe that China and Russia would remain passive. Both would almost certainly take steps to maintain their secured second-strike capabilities, including by deploying countermeasures in the form of anti-satellite weapons or growing their warhead numbers.

This would likely prove more difficult for Russia, given the budgetary and technological constraints it is facing, at least compared to China. Nevertheless, Russia would likely to go to great lengths to maintain the credibility of its strategic nuclear arsenal.

Some analysts, often those writing from the arms control and disarmament camp, often argue that any strategic missile defense project remains technically unfeasible, while simultaneously claiming that it is destabilizing. Others have rightly noted that this dual argument lacks internal consistency: if a system is ineffective — and perceived as such by potential adversaries — it should not be able to generate disproportionate threat perceptions.

My view is that a large-scale missile defense project would be destabilizing precisely because it could prove effective. In recent years, missile defense technology — especially in U.S. systems — has advanced significantly. While the basic task of a kinetic interceptor remains akin to hitting a bullet with a bullet (though at speeds several times higher than those of conventional firearms), modern technology has made this increasingly viable. If the United States moves forward with serious investments in strategic missile defense, China and Russia are almost certain to respond with countermeasures, exactly because they would perceive it as a credible threat to their nuclear arsenals.

Finally, the deployment of such a system could accelerate the militarization of space, potentially prompting other actors to follow suit, an outcome that may not ultimately align with long-term U.S. strategic interests. That being said, U.S. government actors may view the large-scale militarization of space as a foregone conclusion, which may reduce the weight of this argument in internal deliberations.

Opportunity costs

Finally, pursuing a comprehensive space-based missile defense system could divert resources and attention from other, and arguably more pressing and feasible missile defense priorities, most of which are actually part of the broader Golden Dome project.

In the coming years, the United States will face a growing threat from Chinese air-, ship-, and submarine-launched cruise and ballistic missiles capable of targeting high-value military and infrastructure targets. Defending against this type of threat requires a layered air and missile defense architecture, positioned along the U.S. coastline and near critical targets deeper inland.

As the war in Ukraine has demonstrated, while feasible, this form of missile defense is costly. Pursuing it will become even more challenging if already constrained resources are funneled into an extremely costly space-based missile defense architecture. For example, for the cost of a single space-based interceptor (estimated at $100 to $300 million), the United States could procure between 25 and 75 PAC-3 MSE interceptors — systems that offer credible and proven defense against a broad spectrum of Chinese conventional missile threats.

The opportunity cost attached to Trump’s vision is therefore extremely high, and any serious pursuit would likely prove strategically disadvantageous to the United States.