Hegseth authorizes DHS testing of Active Denial System at US-Mexico border

Key points

• Hegseth signed a memo authorizing a seven-month loan of one ADS unit to DHS, starting in September 2026.
• The ADS fires an electromagnetic beam with a range of up to 1,000 meters, penetrating skin to create a burning sensation that triggers an immediate flight response.
• The memo states the system shall not be operated by Department of War personnel, placing full responsibility for use and tactics on DHS.
• DHS can request an extension of the loan after the seven-month period based on operational needs.
• Previous attempts to use ADS at the border were rejected in 2018 by then-Homeland Security Secretary Kirstjen Nielsen.
• The Pentagon notes that while designed as nonlethal, the weapon has caused second-degree burns in two documented incidents due to procedural errors or accidents.

Background

The Active Denial System was developed by the Pentagon between 2002 and 2007 as a nonlethal deterrent. The Air Force began researching directed-energy weapons in the late 1980s. In 2018, former DHS Secretary Kirstjen Nielsen rejected a proposal to use ADS against migrants, citing concerns about treating immigrants like enemy combatants. In July 2025, a Pentagon office published an article arguing in favor of using energy weapons for border security. Recent border security measures under the current administration have included increased military presence and testing of various technologies, including high-energy lasers and microdrones.

How outlets are covering it

Axios emphasizes the legal and safety questions surrounding the potential use of a military weapon against migrants, noting that the authorization does not guarantee deployment. CNN highlights the unprecedented nature of the move, noting that previous administrations and even the current administration's officials had previously rejected or hesitated to deploy ADS due to concerns over harm, legality, and effectiveness. CNN also notes that some Border Patrol agents doubt the need for the tool given low border crossings and increased personnel. The Independent focuses on the fact that Hegseth signed off on the testing, contrasting it with previous American officials who passed on the idea. All sources agree that the ADS is a nonlethal weapon designed to cause pain and repel targets, but they differ on the likelihood and desirability of its deployment. Axios and CNN highlight the potential for injury and legal challenges, while the Independent focuses on the decision-making process. CBP officials, as cited by Axios and CNN, frame the testing as part of a continuous evaluation of new technologies to enhance operational effectiveness and national security.

Why it matters

The approval of testing a military-grade directed-energy weapon at the border raises significant ethical, legal, and safety concerns. It marks a shift in border security strategy, potentially treating migrants as targets of nonlethal weapons rather than individuals seeking asylum. The move could set a precedent for the use of such technologies in other contexts, including domestic unrest. It also highlights the increasing militarization of border enforcement and the willingness of the current administration to test new technologies in high-stakes environments. The potential for injury, even if unintended, could lead to legal challenges and public backlash. The decision also reflects a broader trend of using the border as a 'battle lab' for testing new military and security technologies.

What to watch

DHS will conduct tests of the Active Denial System over the next seven months to develop tactics and evaluate its effectiveness. The outcome of these tests will determine whether DHS requests an extension of the loan or proceeds with deployment. Legal and ethical challenges may arise if the weapon is used in a way that causes injury or is perceived as inhumane. Public and political opposition may increase if the weapon is deployed, particularly if it is used against migrants or in situations where it could cause harm. The Pentagon and DHS will likely monitor the situation closely and may adjust their strategies based on the results of the tests and any legal or public backlash.