Cramer, Sullivan Introduce Iron Dome Act

Senators Kevin Cramer and Dan Sullivan have introduced legislation to begin implementing President Trump’s Executive Order to create a missile-defense shield he calls an Iron Dome for America. The IRONDOME Act would authorize $19.5 billion in FY2026 for a variety of missile defense systems including space-based sensors and space-based missile defense.

Cramer (R-North Dakota) chairs the Senate Armed Services Committee’s Airland Subcommittee and Sullivan (R-Alaska) is a member. Their “Increasing Response Options and Deterrence of Missile Engagement” or IRONDOME Act would authorize funding for several missile defense-related systems. The $19.548 billion includes $60 million for Space Development Agency (SDA) satellite sensors and $900 million for research and development of space-based missile defense.

The name Iron Dome is taken from Israel’s ground-based short-range missile defense system that recently demonstrated its effectiveness in countering Iranian missiles. Israel is a tiny country and Iron Dome is only one part of its missile defense system so really isn’t comparable in scale to Trump’s concept of a multi-layered defense for the United States, but it conveys the point of defending the homeland from missile attacks.

Trump’s Iron Dome for America traces its roots to Ronald Reagan’s Strategic Defense Initiative (SDI) that had a heavy reliance on space-based systems, including space-based lasers to destroy missiles during the boost and mid-course phases of their trajectories. The United States has many space-based systems that support terrestrial military missions, but no space-based weapons capable of destroying incoming missiles.

The White House’s January 27 Executive Order would change that. It directs Secretary of Defense Pete Hegseth to submit within 60 days a “reference architecture, capabilities-based requirements, and an implementation plan for the next generation missile defense shield.”  Concurrently, he is to work with the Director of the Office of Management and Budget to present a budget proposal before the FY2026 budget request is finalized.

The Executive Order mentions several specific space-based elements for this “next generation missile defense shield”: the Hypersonic and Ballistic Tracking Space Sensor Layer (HBTSS), the custody layer of the Proliferated Warfighter Space Architecture, and proliferated space-based interceptors.

Some of those already are under development by SDA, which is part of the U.S. Space Force, or the Missile Defense Agency (MDA).

Two prototype HBTSS satellites were launched for MDA in 2024. SDA has been working on the PWSA for several years. “Proliferated” means that instead of one or few satellites — “big juicy targets” as Gen. John Hyten once called traditional national security satellites — there are dozens or hundreds, making the system as a whole more resilient to attack. The concept is referred to as a proliferated low Earth orbit or pLEO architecture.  SDA is developing a Tracking Layer and a Transport Layer right now, with the Custody Layer and four others planned to be delivered in two-year tranches.

These programs trace their immediate roots to the first Trump Administration, but they build on Reagan’s SDI architecture for a layered ballistic missile defense shield to protect America and her allies from Soviet attack. Announced on March 23, 1983 and dubbed “Star Wars” by its critics, it envisioned ground, air, sea and space-based systems to destroy enemy missiles during their boost/ascent, mid-course, and terminal phases. Cost and technical complexity prevented SDI from moving forward as Reagan proposed, but portions of the program did continue. Prior to SDI, the United States had no capability to intercept incoming missiles, but now has Ground Based Interceptors (GBIs) and Terminal High Altitude Area Defense (THAAD) systems designed to defeat ballistic missiles from “rogue” nations like North Korea or accidental or unauthorized launches. The Navy’s Aegis cruisers also can target incoming ballistic missiles. But those systems are not designed to counter attacks from peer or near-peer competitors like Russia and China.

Over the past 40 years, the threat has changed and so has technology. Trump’s plan resurrects the idea of space-based interceptors for boost-phase intercept, though it doesn’t specify space-based lasers.  Similarly, the Cramer-Sullivan IRONDOME Act is not specific about the type of system.

Although technology has advanced dramatically since the 1980s, developing space-based interceptors that can be relied upon to work the instant they’re needed years after launch, at a cost the nation can afford, remains problematical.

Victoria Samson, Chief Director, Space Security and Stability for the Secure World Foundation, told SpacePolicyOnline.com that it would take “thousands of satellites just to intercept a single missile.”

In order to be able to respond to a solid fueled ICBM in its boost phase, an interceptor would have about two minutes to act. It would require a constellation of thousands of satellites just to intercept a single missile. And that even assumes that it would work properly. Missile defense in general does not have a great track record in testing against ICBMs. Space-based interceptors are a fake capability that hurts U.S. national security because they would take funding and effort away from actual technologies that could work, and harm U.S. efforts in diplomatic discussions. — Victoria Samson

Funding for research and development on space-based missile defense is, in fact, only a small part of the Cramer-Sullivan legislation — $900 million out of $19.5 billion.

The vast majority is for existing terrestrial systems like THAAD, Patriot, and Aegis Ashore. The largest chunk, $12 billion, is for “expansion of missile interceptor fields available at Fort Greely, Alaska, to 80 units with the Next Generation Interceptor.”  NGI is a Ground-based Midcourse Defense (GMD) system currently under development for MDA.  Lockheed Martin was selected as the prime contractor last year.