Trump revives push for space-based interceptors in ‘Iron Dome for America’ edict

President Donald Trump issued an executive order Monday night tasking the Pentagon to build a plan for a multilayered missile defense system underpinned by both space-based sensors and interceptors.

Under the directive, titled “Iron Dome for America,” Secretary of Defense Pete Hegseth is required to develop “a reference architecture, capabilities-based requirements and an implementation plan” to address emerging aerial threats against the U.S. homeland. The strategy, due to the president in the next 60 days, must focus on defense against ballistic, hypersonic, advanced cruise missiles and other aerial platforms.

“Over the past 40 years, rather than lessening, the threat from next-generation strategic weapons has become more intense and complex with the development by peer and near-peer adversaries of next-generation delivery systems and their own homeland integrated air and missile defense capabilities,” the EO states.

The directive comes after Trump promised to create a “great Iron Dome shield” over the United States in June during his presidential campaign, referencing the Israeli air defense system built by Rafael. While Israel’s capability is designed to intercept short-range rockets and artillery, it’s clear that Trump’s vision for America’s own Iron Dome shield considers a greater range of threats and technologies.

Notably, the order calls for development and deployment of “proliferated space-based interceptors” stationed on orbit that can defeat ballistic missiles during the boost stage of flight.

The inclusion of space-based interceptors will likely be a source of contention in the executive order’s execution, Todd Harrison, senior fellow at the American Enterprise Institute, told DefenseScoop. Fielding such weapons has been a controversial matter that was floated by the first Trump administration in 2018, but did not receive traction during President Joe Biden’s term.

The concept for space-based interceptors was a centerpiece of President Ronald Reagan’s Strategic Defense Initiative in the 1980s, which was abandoned due to technological immaturity and expensive price tags at the time. Critics referred to it derisively as a “Star Wars” project. But the cost of putting satellites on orbit has reduced drastically in recent years, largely due to advancements made by Elon Musk’s SpaceX business.

“When Ronald Reagan wanted to do it many years ago, luckily we didn’t. We didn’t have the technology then. It was a concept but we didn’t have” sufficient tech, Trump said Monday evening during remarks to lawmakers at his Trump National Doral resort in Miami. “Now we have phenomenal technology. You see that with Israel, where out of 319 rockets [launched against them] they knocked down just about every one of them. So I think the United States is entitled to that. And everything will be made right here in the USA, 100 percent.”

However, there are still technological limitations to the weapons that require additional study and analysis before the Pentagon can field them at scale, Harrison said.

“If you have a system that’s designed so that there’s always at least one interceptor within range, you could shoot down any one missile. But if someone launches a salvo of two missiles, the second will get through,” he said. “You would have to double the size of your constellation in order to shoot down two at once, and you would have to quadruple it to shoot down four at once. So it quickly becomes cost prohibitive the way it scales.”

Space-based interceptors would be ideal for threats posed by Iran or North Korea, neither of which currently have significant numbers of intercontinental ballistic missiles (ICBMs). But against nations with larger ICBM arsenals like China and Russia — considered by the Defense Department as the United States’ most pressing military adversaries — the weapons aren’t as effective, Harrison added.

Given the growing importance of space as a warfighting domain, however, kinetic and non-kinetic space-based weapons will become more common in missile defense solutions, according to Tom Karako, director of the Missile Defense Project at the Center for Strategic and International Studies. 

“It’s not necessarily going to be 10,000 things, it may be more limited,” Karako told DefenseScoop. “But the genie is out of the bottle. The past paradigms of strategic stability have kind of vaporized and vanished before our eyes over the last decade … The world has changed, and we’re going to have to change with it.”

Trump’s executive order prioritizes several ongoing space-based missile defense programs, as well. It calls for accelerated deployment of the Missile Defense Agency’s Hypersonic and Ballistic Tracking Space Sensor Layer (HBTSS), which is currently expected to become operational by 2035.

The directive also tasks the Space Development Agency to develop a custody layer within its Proliferated Warfighter Space Architecture (PWSA), a planned mega-constellation comprising hundreds of satellites carrying data relay, missile warning and missile tracking capabilities.

Harrison noted that SDA had previously considered incorporating a custody layer into its architecture as part of future tranches, and Trump’s order now gives the agency the green light to move forward.

A deployed custody layer, which continuously tracks and keeps eyes on enemy missile threats, would also contribute to the EO’s directive to deploy capabilities that can defeat missile attacks prior to launch, he added.

“Previously, they planned to just use other people’s systems and make kind of a virtual custody layer,” Harrison said. “I think that’s one of the biggest changes here, is they’re giving [SDA] the go-ahead for that.”

Space-based capabilities aren’t the only elements of Trump’s directive, as the executive order calls for “deployment of underlayer and terminal-phase intercept capabilities postured to defeat a countervalue attack.” That would likely mean bolstering the United States’ arsenal of ground-based interceptors with additional systems already available.

“The foundation for an Iron Dome for America needs to start with air and cruise missile defense,” Karako said. “That’s our biggest gap area. That’s our biggest, near-term vulnerability that we have very little capability against, and so we need to get after that.”

After submitting his plan for homeland missile defense to the White House, Hegseth has been tasked to conduct a subsequent review of theater missile defense postures. Per Trump’s executive order, the follow-on should include options for protecting forward-deployed troops; accelerating provisions of missile defenses capabilities to allies and partners; and increasing international cooperation on relevant technology development, capabilities and operations.

A large question for the Defense Department as it carries out its review will be the cost of developing and deploying such a large missile defense architecture. The order requires an accompanying funding plan that can be examined and included in the upcoming budget request for fiscal 2026, but the EO offers no insight into how much the Pentagon would have to spend.

Some previous cost estimates for a large-scale architecture with space-based interceptors have been upwards of $100 billion, although others have said it could be built for a fraction of that amount.

Harrison estimated the missile defense efforts outlined by Trump would require substantial long-term investment, likely costing billions of dollars per year over at least the next decade.

“That impacts the question of, are they going to request more defense funding overall or will this come at the expense of something else within the defense budget? It’s not clear, because the administration has not been all that forthcoming about their plans for the defense budget overall,” he said.