Trump's Missile Defense Plans: Not Worth the Money or Effort

The United States needs more missile defense, but not what Trump is suggesting.

Picture: Lockheed Martin

This week, Donald Trump announced plans for a major buildup of U.S. missile defense capabilities. This is not entirely surprising, as he repeatedly stated during the campaign that the United States should develop its own “Iron Dome,” referencing Israel’s well-known missile defense system designed to protect against smaller projectiles such as artillery shells, mortar rounds, and rockets.

Of course, unless U.S. border cities were under threat from Canada or Mexico, an Iron Dome-like system would serve little purpose. However, Trump’s plans are far more ambitious, focusing on “next-generation aerial threats,” including ballistic, cruise, and hypersonic missiles, as well as proposals for “space-based interceptor” systems and advanced “terminal phase intercept” capabilities.

Trump’s broader missile defense agenda includes additional initiatives that are not worth detailing individually. The key takeaway is that his envisioned missile defense posture would go beyond the current capability of defending against small-scale or accidental nuclear attacks. Instead, it aims to counter large-scale nuclear strikes, including full-scale “countervalue” attacks targeting American cities.

If Trump’s administration—or any future administration—were to realize such a missile defense capability, it would fundamentally transform international relations and nuclear warfare. However, as I explain below, achieving such a system is highly unrealistic, and its pursuit would be both inefficient and strategically self-defeating.

Complex, expensive, and easy to counter

The United States already deploys strategic missile defense systems designed to intercept incoming nuclear warheads before they reach the U.S. mainland. This system consists of 44 Ground-Based Interceptors (GBIs) stationed at two sites: Fort Greely, Alaska, and Vandenberg Space Force Base, California.

Assuming an optimistic individual intercept probability of 80–90%, at least two—but ideally three—interceptors would need to be allocated per incoming warhead to ensure a high probability of interception. Under current numbers, this means the system could realistically intercept only 14 to 22 warheads. While that might be sufficient to counter a small-scale attack or an accidental launch, it is nowhere near capable of defending against Russia’s approximately 1,600 deployed strategic nuclear warheads or China’s estimated 600 deployed strategic nuclear warheads.

To deny large-scale attacks, the U.S. GBI arsenal would have to expand drastically. In principle, this is feasible—the technology is well-understood, and production could be scaled. The problem is cost.

The next-generation GBI, currently in development by Lockheed Martin, is expected to cost at least $70 million per unit, though estimates suggest it may be closer to $90–100 million. Even assuming the lower-end estimate of $70 million and a doctrine that requires three interceptors per enemy warhead to ensure redundancy and near-certain interception, the financial burden would be staggering:

• $126 billion to counter China’s nuclear arsenal

• $336 billion to counter Russia’s nuclear arsenal

• $462 billion to counter both arsenals simultaneously

And this is a highly conservative estimate. It assumes warhead numbers remain constant, which is unlikely—China is actively expanding its arsenal, and Russia may follow soon. It also does not account for the cost of enabling capabilities such as satellites, radar systems, the construction and maintenance of dozens of interceptor bases, or the personnel required to operate them.

In total, this would be a multi-trillion-dollar endeavor. Where exactly is the U.S. supposed to find that kind of money, especially amid all the other priorities?

The other option, as mentioned in Trump’s announcement, would be to invest in space-based interceptors, particularly those designed for boost-phase interception. The advantage of this approach is that it targets the delivery vehicle before nuclear warheads separate, meaning a single interception could neutralize multiple warheads at once, reducing the number of interceptors needed. This could theoretically be achieved through satellite-launched interceptors or space-based laser systems.

The problem is that, unlike ground-based interceptors, this technology is neither mature nor anywhere near deployment. While laser weapons are becoming increasingly effective against small, short-range targets, we are nowhere close to developing operational laser systems capable of delivering enough energy to destroy ICBMs at distances of dozens or even hundreds of kilometers, which would likely be necessary for a space-based system to be effective. Deploying kinetic interceptors would likely be more doable within a reasonable timeframe, though integration into a space-based system would still present substantial challenges.

Scale is another major issue. Orbiting satellites do not remain stationary, meaning that to maintain continuous coverage over China and Russia, hundreds—if not thousands—of satellites would be required. For example, keeping between one and eight interceptors over China at all times would require a constellation of over 1,000 satellites. The cost of developing, launching, and maintaining such a system, along with the necessary R&D and supporting infrastructure, would likely run into the hundreds of billions, if not trillions, of dollars. Even then, submarine-launched nuclear weapons could exploit the vastness of the oceans to simply move beyond the coverage area, negating the system’s effectiveness.

Beyond the technological and financial challenges, the biggest issue is that strategic missile defense can be easily countered. For example, if the U.S. were to deploy 4,800 ground-based interceptors to counter Russia’s 1,600 deployed nuclear warheads, Russia could simply increase its warhead count by removing warheads from storage and maximizing the upload capacity of its ICBM launchers, potentially expanding its arsenal to 3,000 warheads or more. Similarly, if the U.S. managed to deploy a space-based missile defense system, nuclear-armed adversaries could invest in a large number of anti-satellite weapons, both kinetic and non-kinetic, to disable or destroy the network.

Under no circumstances would China, Russia, or any other nuclear power passively allow their second-strike capability to be neutralized. They would go to extraordinary lengths to protect their nuclear deterrents. Assuming otherwise is pure hubris, detached from reality.

Missile defense investments that make sense

This does not mean that missile defense is unnecessary or always a poor investment. The United States absolutely needs stronger missile defense capabilities for both theater deployment and homeland defense. However, pouring resources into strategic missile defense to counter large-scale nuclear attacks is a losing game that diverts funding from other, more pressing priorities.

For instance, in an Asia-Pacific contingency, the U.S. needs a robust missile defense system to counter Chinese cruise and ballistic missiles targeting forward-deployed bases and allies, including short-, medium-, and intermediate-range ballistic missiles. Effectively fulfilling this role requires greater investment in missile defense systems specifically optimized for this mission, including NASAMS, Patriot, Aegis, and THAAD.

Similarly, while China does not currently field a conventional missile capability that can credibly threaten U.S. homeland targets, it is believed to be developing a longer-range land-attack cruise missile capability for platforms such as the Type 093B guided missile submarine and the Type 055 destroyer. Countering this emerging threat will require additional missile defense systems. These types of investments should clearly take priority over what is ultimately a futile pursuit of large-scale strategic missile defense.