Katie Arrington, the Pentagon’s acting chief information officer (CIO), told lawmakers on May 8 that executing on President Donald Trump’s “Golden Dome” missile defense initiative will require the Department of Defense (DoD) to maintain control over vital portions of the 3 gigahertz (GHz) band of radio frequency spectrum.
“It is critical for national security,” Arrington said during a House Armed Services Subcommittee hearing on Thursday. “The only way we can achieve Golden Dome right now is having the lower three of the spectrum.”
The DoD currently controls us of the 3.1 to 3.45 GHz band – commonly referred to as the “lower three” — to operate radar and missile defense systems. Arrington emphasized the essential role this portion of the spectrum plays in enabling more than a thousand platforms and weapons systems.
“The lower three of spectrum is where we carry about 1,100 different platforms and weapons systems to protect national security,” Arrington said. “Those are prized, critical capabilities that we cannot lose … That area of the spectrum is golden, and we need to protect it to maintain national security.”
According to Arrington, the Golden Dome initiative ordered by President Trump earlier this year seeks to bolster national defense through advanced sensing – which includes spectrum-based technologies – that aim to detect and neutralize threats before kinetic (physical) conflict arises.
To achieve that vision, Arrington said multiple Pentagon offices – including the Chief Digital and Artificial Intelligence Office, the Office of the CIO, the Research and Engineering Directorate, and the Defense Advanced Research Projects Agency – are actively collaborating to ensure optimal use of the spectrum.
This defense priority, however, stands at the center of a broader, long standing, and contentious policy debate over how much spectrum the military should retain versus share or relinquish to the private sector.
Arrington explained that while spectrum sharing is possible, “we do need to look at ways to share it in a sensible, realistic manner.” Proponents of spectrum sharing are pushing for new models of shared use, including a “highly dynamic” spectrum sharing (DSS) framework.
Arrington acknowledged the promise of DSS but urged caution.
“It is yet to be determined, and it is prudent to ensure protection of national security for the taxpayer in protecting the lower three,” she said. “The lower three is not in that mix.”