The U.S. government set off conventional explosives inside a tunnel deep in the Nevada desert this week in a test designed to replicate a so-called “decoupled” nuclear detonation. Data collected is now being used to help improve methods for detecting this kind of nuclear testing. Just earlier this year, American authorities accused China of using decoupling to conceal new nuclear tests despite the country’s stated moratorium on such activities.

The test, which involved the use of chemical high-explosives and radiotracers, was conducted yesterday inside P Tunnel in Area 12 of the Nevada National Security Site (NNSA), according to a press release from the National Nuclear Security Administration (NNSA). The NNSS, which is situated within the boundaries of the U.S. Air Force’s Nevada Test and Training Range (NTTR), is used for a wide variety of testing purposes today. An agency under the Department of Energy, NNSA’s main jobs are to oversee the development and production of nuclear weapons, as well as manage America’s nuclear deterrent stockpile.

“This experiment is especially focused on further enhancing the U.S. capabilities to detect a ‘decoupled’ explosion,” per NNSA’s release. “Data collected from the experiment will be used to validate scientific models and refine algorithms that are critical to U.S. nuclear explosion detection efforts.”

“Just as a stealth aircraft looks smaller on radar, decoupling can greatly muffle the signals detected by nuclear detection sensors, making a large explosion appear smaller,” the release explains. “In a conventional, or ‘coupled,’ underground nuclear test, a device is placed deep in a hole in close contact with the rock, allowing much of the explosion’s shockwave to reach sensors. In a decoupled test, by contrast, the device is detonated inside a large underground chamber, substantially reducing the explosion’s seismic signature.”

“In this experiment, researchers gathered measurements using a broad suite of advanced sensors, including accelerometers, seismometers, infrasound sensors, electromagnetic sensors, chemical and radiotracer samplers, and meteorological sensors,” it adds. ”Together, these measurements will improve scientists’ understanding of the signatures produced by underground explosions and strengthen the United States’ ability to detect and characterize nuclear explosive events.”

The U.S. already maintains a U.S. Atomic Energy Detection Systems (USAEDS) network, which is overseen by the U.S. Air Force Technical Applications Center (AFTAC). USAEDS is made up of more than 3,600 sensors positioned around the world. USAEDS is also tied in with the International Monitoring System (IMS), which is managed by the organization responsible for overseeing the Comprehensive Nuclear-Test-Ban Treaty (CTBT). AFTAC also supports the mission to monitor for potential nuclear testing globally using a fleet of specially configured WC-135R Constant Phoenix aircraft. In addition, those planes are used to help keep watch for unusual spikes in atmospheric radiation that could point to nuclear or radiological accidents or other incidents leading to the spread of potentially dangerous radioactive material.

With regard to the USAEDS network specifically, “once a disturbance is detected underground, underwater, in the atmosphere or in space, the event is analyzed for nuclear identification, and the findings are reported to command authorities,” according to AFTAC’s website.

As mentioned, the U.S. government has accused its Chinese counterparts of using decoupling to conceal new nuclear testing, and NNSA’s press release draws explicit attention to these allegations. At the annual Conference on Disarmament in Geneva, Switzerland, in February, Thomas DiNanno, Under Secretary of State for Arms Control and International Security, said that China had conducted at least one such test at Lop Nur on June 22, 2020. The Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) subsequently said the IMS had not detected an event matching that description at that location on that date. For its part, the Chinese government has denied the accusation.

The social media posts below include satellite imagery showing activity at Lop Nur that could point to new nuclear testing activities in recent years.

参考
Satellite Imagery Analysis of China’s Alleged 2020 Nuclear Test at Lop Nurhttps://t.co/aafvU5Szh7
CSIS 20260213
ROLES SAT ANALYSIS No.7　中国に核実験実施の動き ー Lop Nur核実験場の画像分析 ーhttps://t.co/n66yYk0hLg
ROLES 20250522

— KAROTASU (@type36512) May 24, 2026

While China is a signatory to the CTBT, the country has never ratified it. The Chinese government last acknowledged a critical-level nuclear test in 1996, after which a self-imposed moratorium was put in place, at least publicly. As an aside, the United States has also signed, but never ratified, the CTBT, and has a similar self-imposed moratorium on nuclear testing since 1992. It is worth noting that the treaty does not ban so-called sub-critical testing, which involves fissile material, but does not result in a full-fledged nuclear reaction.

Last week, The Wall Street Journal reported that the Trump administration has been holding new talks with the Chinese government regarding various aspects of the country’s massively and rapidly expanding nuclear arsenal, including the testing allegations. That story immediately preceded a state visit by China’s President Xi Jinping to Washington, D.C., to meet with Trump.

“The discussions between American and Chinese officials have centered on measures to reduce nuclear risks and haven’t been aimed at negotiating a formal arms-control pact, an effort Beijing has sharply rebuffed in the past,” according to that report. “The Trump administration has begun to highlight the possibility of implementing new verification measures.”

“Independent experts say seismic instruments might be placed on or near test sites,” The Journal‘s story also noted. “Another possibility, which was floated during the Biden administration, is to install radiation-detection equipment at test sites.”

NNSA’s announcement about the test at the Nevada National Security Site is certainly an example of the development underway already of new means of verification that could be deployed at sites around the world.

The United States has separately accused Russia of conducting lower-yield nuclear testing in secret in the past. Russia is a signatory to the CTBT and had previously ratified it. In 2023, President Vladimir Putin revoked that ratification in line with the provisions of a law passed by the country’s parliament, or Duma.

President Trump has also floated the idea of the resumption of U.S. nuclear testing in response to Russian and Chinese activities, though other U.S. officials have downplayed the possibility of doing so. The United States is otherwise in the midst of a huge nuclear modernization effort that impacts the air, sea, and land-based legs of the deterrent triad. American authorities are also now pursuing these efforts in an environment fully unbounded by relevant arms control agreements following the sunset of the New Strategic Arms Reduction Treaty (New START) earlier this year.

The Russian government has said it is ready to conduct new nuclear tests if the United States pursues this course of action. The last official nuclear test in Russia came in 1990 right before the fall of the Soviet Union.

“It takes nuclear expertise to detect nuclear activities and experiments like these [to] ensure America remains unmatched in detection,” NNSA Administrator Brandon Williams said in a statement yesterday in light of the test in Nevada. “The Trump Administration has made it clear that the United States will lead from a position of strength. You cannot evade American innovation. With this experiment, we are sending a clear message: under this administration, America will never be outmatched.” 

Contact the author: joe@twz.com

The post U.S. Mimics “Decoupled” Nuclear Detonation By Blowing Up A Tunnel Conventionally appeared first on TWZ.

The Pentagon has announced plans for a new functional combatant command, very broadly akin to U.S. Special Operations Command (SOCOM) or U.S. Space Command (SPACECOM), but for operational activities involving autonomous and robotic capabilities. Secretary Pete Hegseth has also announced new initiatives to help further accelerate the fielding of uncrewed systems in the air, at sea, and on land, as well as to explore future warfighting challenges. All of this builds on previous and long-overdue efforts to prioritize the fielding of various tiers of drones, as well as artificial intelligence (AI) and other emerging technologies, across domains, but there are questions about how these new efforts will translate into tangible developments.

Secretary Hegseth unveiled plans for what is tentatively dubbed Autonomous Warfare Command (AUTOWARCOM), as well as the aforementioned initiatives, called Project Agincourt and Project Meridian, during a speech to service members today at the U.S. Marine Corps’ base in Quantico, Virginia. Hegseth called this a State of the Force address, and said he planned to make it an annual event.

.@SECWAR “Today, at my direction—we are announcing the creation of Autonomous Warfare Command, or AutoWarCom:

A new 4-star combatant command—with service-like authorities—built to scale autonomous and robotic capabilities across the Joint Force in the fastest peacetime shift in… pic.twitter.com/kYWBxy6Dij

— DOW Rapid Response (@DOWResponse) September 30, 2026

“At my direction, we are announcing the creation of Autonomous Warfare Command, or AUTOWARCOM, a new four-star combatant command with service-like authorities built to scale autonomous and robotic capabilities across the joint force in the fastest peacetime shift in modern military history,” Hegseth declared. “Drone warfare supercharged by SI-enabled targeting is the biggest battlefield revolution in generations. You already know that. Yet when I was sworn in to the Department of Defense, there was scant urgency in this domain.”

“SI” here stands for “super intelligence,” a term the Trump administration is now using in place of AI.

Hegseth called attention to the Drone Dominance initiative he unveiled last year, as well as the establishment of Joint Interagency Task Force 401 (JIATF-401), as examples of steps the Department has already taken in this regard. JIATF-401 is notably focused on counter-drone capabilities, as you read more about here.

“It’s a good start, but it’s certainly not enough. The pace of war is changing faster than the process to support it. Cheap compute, super intelligence, and advanced commercial manufacturing have enabled the proliferation of low-cost, high-precision strikes,” Hegseth continued. “For 40 years, the United States relied … primarily on expensive weapons that placed quality over quantity. Now, that approach gave us a lot of enormous advantages, and we need to preserve those capabilities. But today we need both quality and quantity. The term you know is high-low mix. An analogy is a thunderstorm. We need bolts of lightning high, our existing high-end kill chains capable of striking unexpectedly and decisively. We also need steady wind and rain, mass drones and other autonomous attritable systems that flip the cost exchange and impose unrelenting pressure on an adversary on the battlefield.”

Hegseth highlighted lessons learned from the ongoing conflict in Ukraine as underscoring these points.

.@SECWAR "Ukraine’s lesson is not that one type of drone wins wars but rather the need for a purpose-built system that maximizes the ability to adapt.

We will fuse procurement with operations at scale – and allow our warfighters, engineers, and entrepreneurs to learn, adapt, and… pic.twitter.com/x7iNMAbU0t

— DOW Rapid Response (@DOWResponse) September 30, 2026

“So today, with Autonomous War Command, AUTOWARCOM, we institutionalize and we supercharge the era of SI, robotics, and autonomous systems, all in order to win,” he added.

A memo the Pentagon has now released makes clear that the establishment of this command is contingent on Congressional approval, and the current goal is for it to be established by October 1, 2027.

“Autonomous Warfare Command will define joint needs and integrate Service-provided forces in support of geographic combatant commanders,” the memo also notes. “It will test equipment and force designs with realistic opposition in demanding exercises and rugged environments, modify rapidly, and field what works. We must build a wartime arsenal whose main product is adaptation at the edge.”

Many questions remain to be answered about how these activities will work with what’s already being done within the individual services, and how all of that will translate into operational activities. Part of Project Agincourt’s role will be working to help answer the questions above. The name here is a reference to the battle in 1415 in which British forces prevailed over their French opponents, famously in part through the application of a particular military technology, the longbow.

The office of the Direct Reporting Portfolio Manager for Unmanned Systems (DRPM-UxS) will lead this initiative. Owen West, head of the Pentagon’s Defense Innovation Unit (DIU), and U.S. Navy SEAL Senior Chief Max Strasiser are set to serve as the Chief Executive Officer and Chief Operating Officer of the DRPM-UxS, respectively.

Project Agincourt will also “prototype a new construct called warfighting acquisition, not just acquisition that happens at the Pentagon,” according to Hegseth. “This model fuses operators with entrepreneurs in rapid adaptation cycles while distributing decisions and dollars closer to frontline units, to combatant commands. Realistic training exercises, and when possible, the crucible of combat, will be used to compress innovation timelines and scale what works.”

“Also today, we are phasing in new MOS [Military Occupational Specialty] frameworks within each military department to support our shift to autonomy,” the Secretary also noted during his speech in the context of Project Agincourt and the plan for AUTOWARCOM. “We need institutional knowledge and career paths for a new generation of autonomous warfighters.”

Project Meridian sits adjacent to these efforts and has a broader mandate to explore ways to ensure the U.S. military maintains its technological edge on future battlefields.

“Project Meridian, the future of warfare, is not about developing new strategies or new policies. We already do that. Rather, its purpose is to creatively look to the future, and identify the domains that we must conquer, and capabilities we must master,” Hegseth said. “We need to be looking forward into the future to achieve technological and military dominance on the battlefield for decades to come. It is futuristic on purpose. Their work will be focused on discovering, developing, and fielding the weapons and systems that our children and our grandchildren will need in their lifetimes, without any creative limitations or restrictions, on any future battlefield, from under the Earth to beyond the Moon.”

.@SECWAR “Today, at my direction—I am announcing Project Meridian, an effort led by America’s best minds to study the future of warfare.

Under the leadership of @USWREMichael, Project Meridian will be co-led by three of our nation’s best minds: @elonmusk, @PalmerLuckey, and… pic.twitter.com/4DyurVpkUZ

— DOW Rapid Response (@DOWResponse) September 30, 2026

“Project Meridian will study the battlefields of the future, identify which weapons and technologies warfighters will need to harness to dominate in these environments, and propose actionable solutions to start developing, testing and fielding these capabilities such that America will have overmatch for the 21st century and beyond,” according to a separate memo the Pentagon put out today. “The Joint Staff and all services should be prepared to connect their future warfare efforts and research to Project Meridian.”

Furthermore, “Project Meridian will leverage critical perspectives from outside the Pentagon, drawing upon a group of top technologists, innovators, business leaders, policy makers, and national security experts,” according to the memo. “Project Meridian’s primary function will be to map the trajectory of future warfare, identify critical capability gaps, and propose actionable solutions in furtherance of the identified goals in the 2026 National Security Science and Technology Strategy.”

This is also very much a near-term initiative, with Hegseth demanding a final report no later than 120 days from now, or January 28, 2027. The Pentagon’s Chief Technology Officer, Emil Michael, has been directed to set up this project. Today, Hegseth also named Elon Musk, Palmer Luckey, and Newt Gingrich as key members.

Elon Musk, founder of SpaceX, which dominates the commercial space launch and services market globally, as well as the host of other companies, has had an on-again-off-again relationship with the Trump Administration. Palmer Luckey is another entrepreneur now best known for founding Anduril, which has increasingly been a major player in the U.S. defense industry. Newt Gingrich, a highly influential member of Trump’s Republican Party and former Speaker of the U.S. House of Representatives, has more recently become an outspoken advocate of advancing AI technology in the United States.

The inclusion of Musk and Luckey does raise ethical questions, as they both lead companies with major U.S. government contracts already, and which could be in line to see more opportunities based on Project Meridian’s findings. What guardrails might be put in place to prevent conflicts of interest is unclear.

To reiterate, it remains to be seen how all of these efforts will progress and how, or if, they will ultimately translate to more tangible developments. The U.S. military has a long history now of launching high-profile initiatives that still struggle to demonstrate real progress, despite widespread support for accelerating the fielding of uncrewed systems, AI, and other advanced technologies. The Pentagon has certainly produced tangible results through other organizational shifts in recent years, including the aforementioned Drone Dominance initiative and JIATF-401, as well as the Replicator initiative under President Joe Biden.

At the same time, there are real potential hurdles to these new plans. The Pentagon has itself already acknowledged that support from Congress will be key to the AUTOWARCOM vision. Annual budgeting, and the uncertainty that often surrounds that will also be a factor. There is also the matter of efforts to expand the U.S. defense industrial base. The limitations of existing U.S. industrial capacity and supply chains have already become a matter of national debate in light of concerns about dwindling stockpiles of critical munitions as a result of the ongoing conflict with Iran, as well as a succession of other global crises in recent years.

During his speech, Hegseth called attention to efforts to broaden the defense industrial base with new, smaller firms, as well as agreements with large established contractors to expand on their existing capacity. He also highlighted the Trump administration’s $1.5 trillion defense spending plan for Fiscal Year 2027 and issued a new call on Congress to pass an additional $350 billion reconciliation package.

With today’s announcements, the Pentagon has certainly reinforced its commitment to expanding the fielding of uncrewed and other high-tech capabilities across all branches of the U.S. military, but there is clearly work still to be done to turn those visions into realities.

Contact the author: joe@twz.com

The post Vision For New Autonomous Warfare Command Laid Out By Pentagon appeared first on TWZ.

The U.S. Air Force is looking at adding a missile warning system (MWS) to its new F-15EX Eagle II fighters. This will give the aircraft a way to optically detect incoming missile threats, especially passively guided ones like heat-seeking infrared-guided missiles, which they currently lack. The continued absence of an MWS has become more pronounced in light of recent combat experiences over Iran.

The F-15EX is derived from earlier F-15 variants that all have MWSs, and it had seemed logical to expect the Eagle II would feature this capability. So it was puzzling when the first examples rolled out without such a system, and no apparent plans to install one on a jet already costing upwards of $100 million. The omission has been glaring for years now, especially given that the aircraft has all the provisions for such a system, including blanked-over spots for the sensors.

The Air Force has 22 Eagle IIs in inventory now and currently plans to acquire a total fleet of 267 of the jets. The aircraft’s manufacturer, Boeing, is on contract now to build 120 F-15EXs, including a lot of 22 jets through a new $2.38 billion deal also announced yesterday.

Now, the Air Force Life Cycle Management Center’s (AFLCMC) Fighters & Advanced Aircraft Directorate “is seeking sources for the procurement of an operationally qualified threat missile launch and approach warning system for rapid integration into the United States Air Force (USAF) F-15EX Eagle II fighter aircraft,” per a contracting notice put out yesterday. “The MWS must alert the F-15EX aircrew to the presence of missiles that may threaten the aircraft without unreasonably distracting the aircrew with false alarms.”

As mentioned, the F-15EX is already configured to accommodate an MWS, inside and out, something AFLCMC’s notice emphasizes. This is a result of the Eagle II having been directly derived from the F-15QA variant for Qatar, which itself was an outgrowth of the F-15SA for Saudi Arabia. While many of the F-15EX’s advances come from these aircraft, the first F-15 variant to get an MWS was actually Singapore’s F-15SG. The Advanced Eagle line and the F-15SG are part of Boeing’s extended F-15E Strike Eagle family.

“The MWS must use the six (6) pre-existing F-15EX sensor locations, data cables, power cables, and cooling,” the contracting notice says. “It must be easily, safely, rapidly, and organically installable and removable in the field by USAF military aircraft maintenance personnel without requiring any change to aircraft configuration beyond installation of MWS line replaceable units (LRUs) in the six (6) pre-existing locations in the aircraft dedicated for missile warning.”

The most visually prominent of those pre-existing sensor locations are two horn-like sponsons, one on each side of the forward fuselage right below the cockpit canopy. There are two more locations at the ends of the jet’s tail booms. The last two locations are situated so additional sensors can face straight up and down to provide total 360-degree coverage.

The sources sought notice does not mention any specific MWS and invites prospective vendors to submit proposals. It also stresses that the Air Force is still in the “market research” phase of the contracting process and that it “does not constitute [a] solicitation and shall not be construed as a commitment” to buy such a system.

The F-15SA uses the AN/AAR-57 Common Missile Warning System (CMWS), and this system is understood to also be found on the F-15QA. Beyond F-15 variants, versions of the AN/AAR-57, for which BAE Systems is currently the prime contractor, are fielded today on a wide variety of other fixed-wing aircraft and helicopters, including various types in U.S. military service. CMWS variants are notably found across the U.S. Army’s AH-64, UH-60, and CH-47 helicopter fleets.

All versions of the CMWS consist of several electro-optic missile sensors (EOMS), the number of which varies from platform to platform, linked to a central electronic control unit (ECU). The system is also designed to be integrated into larger defensive suites.

While the AN/AAR-57 is a proven system with years of successful integration on the F-15 and other platforms, it is just one option of the open market today. The Air Force could choose to take another route, possibly with a new system that offers added functionality.

The addition of any MWS will give the F-15EX a valuable, if not increasingly critical, boost in defensive capability. The Eagle II does already have an extremely powerful self-protection suite, including the Eagle Passive/Active Warning Survivability System (EPAWSS). However, it is heavily geared toward defending against radar-based threats that pump out signals that can be detected and jammed. Infrared-homing anti-air missiles zero in on their targets passively.

In general, MWSs also typically make use of passive infrared sensors to spot the heat plumes of missile launches and the thermal signatures of those threats as they continue their approach. BAE Systems says current-generation versions of the AN/AAR-57 are sensitive enough to detect infantry anti-armor rockets being launched, as well as small arms fire from the ground, under the right circumstances. Though an MWS is not an active countermeasure unto itself, the early warning it provides gives critical time to deploy flares or employ other defensive capabilities, or just take evasive action.

TWZ touched on all of this last month after The New York Times reported new details about the shootdown of an F-15E Strike Eagle over Iran in April. A shoulder-fired, heat-seeking surface-to-air missile, also known as a man-portable air defense system (MANPADS), is said to have been responsible, though this remains unconfirmed. The Strike Eagle also lacks an MWS. The Times‘ story said that the F-15E’s defensive suite provided the crew with only half a second of warning. As we noted at the time, it would actually have provided no warning given that the Strike Eagle also lacks an MWS.

Even before the current conflict with Iran broke out, TWZ had questioned the F-15EX’s lack of this capability given the general focus on increased survivability to match expanding threat ecosystems globally. EPAWSS is already a reflection of that reality, and could be made even more capable when tied together with an MWS. In May, we had reached out to the Air Force about any plans to integrate an MWS onto the F-15EX in light of observations from the ongoing conflict with Iran. The service told us then that it had no details to share. Whether the service now has any plans to add MWSs to the Strike Eagle fleet, which would require more significant integration work, is also unknown.

Buying F-15EX and not springing for the missile approach warning system is absolutely the dumbest thing. $100M fighter, but let's save a few bucks on a key defensive advantage. You are not always going to get a radar spike from a threat, even at altitude.

— Tyler Rogoway (@Aviation_Intel) April 4, 2026

They also didn't buy conformals for the first EXs. So silly.

— Tyler Rogoway (@Aviation_Intel) April 4, 2026

Infrared homing anti-air missiles, as well as air defense systems that use passive infrared sensors for target detection and cueing, are certainly not threats limited to Iran. In Yemen, Iranian-backed Houthi militants have been making good use of these capabilities for years now, something else we have explored in great detail in the past. The Houthis claimed to have downed a Saudi Arabian F-15 just earlier this month and, per a now-long standing modus operandi, subsequently released video captured through a ground-based forward-looking infrared (FLIR) system as evidence. The group also shared images of the wreckage of what looked to be an F-15SA Advanced Eagle, underscoring the dangers posed even to aircraft equipped MWSs.

Onboard footage of a Houthi SAM system shooting down a Saudi F-15 overnight over Yemen’s Marib province. pic.twitter.com/6mh23B2Ovu

— OSINTtechnical (@Osinttechnical) September 16, 2026

These threats are not limited to the Middle East more broadly, either, and are only increasingly likely to be encountered in future conflicts globally. The emergence of ever-more capable and longer-range anti-air missiles with infrared or dual-mode guidance systems is a significant factor in all this. Expanding use of passive infrared search and track (IRST) systems on aircraft and infrared sensors on ground-based air defense systems are part of this larger equation, as well.

How the Air Force ultimately decided to proceed with the integration of an MWS onto the F-15EX fleet remains to be seen. However, the Eagle II’s lack of this capability is only becoming more striking, especially in light of the conflict with Iran.

Contact the author: joe@twz.com

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