Electromagnetic spectrum operations explained: EMSO, JEMSO, and EMBM

Every modern military capability depends on the electromagnetic spectrum. Radios, data links, radars, satellite terminals, GPS receivers, identification systems, precision weapons, and the sensors that cue them all transmit, receive, or do both. For most of the Cold War and the years after it, the Department of Defense treated two parts of that problem separately. Electronic warfare (as it was then called) belonged to operators and planners focused on jamming and detecting the enemy. Spectrum management belonged to communicators and frequency managers focused on making sure friendly systems could get an assignment and not interfere with each other.

Those two communities are now supposed to work as one. The current doctrinal term is electromagnetic spectrum operations, or EMSO, and at the joint level it is joint electromagnetic spectrum operations, or JEMSO. Since 2020 the department has rewritten its joint doctrine, issued a new superiority strategy, signed a classified implementation plan, stood up a new joint center under U.S. Strategic Command, and started fielding a joint battle management tool for the spectrum. Congress has written much of this into law. The Government Accountability Office has spent more than a decade documenting how hard it is to make any of it stick.

This article walks through what EMSO and JEMSO mean, how the doctrine and terminology evolved, how each service organizes for the mission, what electromagnetic battle management is supposed to do, and where the public record says the effort still falls short. Everything here comes from public, unclassified sources. Where details of plans, capabilities, or readiness are classified or simply not published, that is stated plainly.

What EMSO and JEMSO actually mean

Joint doctrine defines EMSO in terms of four verbs: coordinated military actions to exploit, attack, protect, and manage the electromagnetic environment. The first three map to the traditional pieces of electromagnetic warfare. The fourth is spectrum management. Putting all four under one heading is the whole point of the concept. A commander does not get to treat jamming plans and frequency plans as unrelated staff products, because a friendly jammer and a friendly radio net competing for the same band is a planning failure, not bad luck.

JEMSO is the same idea applied to a joint force. Joint Publication 3-85, Joint Electromagnetic Spectrum Operations, describes JEMSO as the electromagnetic warfare and joint spectrum management activities a joint force commander uses to exploit, attack, protect, and manage the electromagnetic operational environment in pursuit of the commander's objectives. The emphasis on the joint force commander matters. Each service brings its own emitters, sensors, and EW systems into a theater, and someone above the services has to decide who gets which frequencies, which emitters are restricted, and when offensive effects can be used without blinding friendly forces.

The electromagnetic operational environment

Doctrine uses the term electromagnetic operational environment (EMOE) for the conditions a force actually faces in a given area and time: friendly, adversary, neutral, and civilian emitters, plus natural phenomena. In a contested region that includes adversary jammers and direction-finding sensors hunting for friendly emissions. Building an accurate picture of that environment is one of the hardest parts of the job.

Electromagnetic warfare and its three divisions

Electromagnetic warfare (EW) is military action involving the use of electromagnetic and directed energy to control the spectrum or to attack an enemy. It has three divisions:

Electromagnetic attack (EA): using electromagnetic energy, directed energy, or anti-radiation weapons to degrade, neutralize, or destroy enemy personnel, facilities, or equipment. Jamming and deception are the familiar examples.
Electromagnetic protection (EP): actions that protect friendly people, facilities, and equipment from the effects of friendly, neutral, or enemy use of the spectrum. Emission control, frequency agility, low probability of intercept waveforms, and hardening all fall here.
Electromagnetic support (ES): actions to search for, intercept, identify, and locate sources of radiated electromagnetic energy for immediate threat recognition, targeting, and planning. ES overlaps technically with signals intelligence, but the distinction is purpose and authority: ES supports the operational commander's immediate needs, while SIGINT operates under intelligence authorities.

Readers who learned the field before 2020 will remember these as electronic attack, electronic protection, and electronic warfare support. The functions did not change. The names did, and the reason is covered below.

Spectrum management

The fourth verb, manage, covers the planning, coordination, and deconfliction of spectrum use so that friendly systems can operate as intended. That includes frequency assignment and allotment, host nation coordination, interference resolution, and the creation and maintenance of the Joint Restricted Frequency List (JRFL), which identifies frequencies that must be protected from friendly EA, such as critical command nets or frequencies being exploited for intelligence. Joint doctrine now uses the phrase joint electromagnetic spectrum management operations for this work at the joint level.

From "electronic" to "electromagnetic": how the doctrine evolved

The current framework is relatively young. Understanding what it replaced explains a lot about why implementation has been slow.

Before 2020

Until 2020, joint doctrine covered the two halves of the problem in separate publications. JP 3-13.1, titled Electronic Warfare, was last revised in 2012 and sat in the 3-13 information operations family. JP 6-01, Joint Electromagnetic Spectrum Management Operations, also dated 2012, sat in the communications family. Different staff sections owned each one. EW cells generally lived in operations or information operations channels. Spectrum managers generally lived in the J-6. The two communities trained separately, used different tools, and often met for the first time in a theater when something interfered with something else.

Strategy followed a similar split. DoD issued an Electromagnetic Spectrum Strategy in 2013 and an Electronic Warfare Strategy in 2017. GAO later found that neither was fully implemented. Of 23 recommendations derived from the 2013 strategy, GAO reported that only three had been completed by January 2019, more than five years after publication.

The operational context pushed in the same direction. Russian operations in Ukraine after 2014 and in Syria after 2015 showed adversary EW jamming communications and GPS and locating emitters for targeting. GAO's 2020 report cited Defense Intelligence Agency characterizations of Russian EW as world-class. Two decades in Iraq and Afghanistan, focused on countering radio-controlled IEDs, had left the U.S. force less practiced at fighting for spectrum access against a peer.

JP 3-85 (May 2020)

On 22 May 2020, the Joint Staff published JP 3-85, Joint Electromagnetic Spectrum Operations. It superseded both JP 3-13.1 and JP 6-01 and consolidated EW and spectrum management into one joint publication. Defense press at the time noted the conceptual shift: the publication treats the spectrum as a maneuver space in which the joint force must gain and keep freedom of action, not simply as a utility to be allocated.

The key changes, at the level that is publicly described, were these:

EW and spectrum management were folded into a single framework, JEMSO, with a single planning process tied into the joint planning process.
The publication defined EMS superiority as the degree of control in the spectrum that permits the conduct of operations at a given time and place without prohibitive interference, while affecting an adversary's ability to do the same.
It described joint staff organizations for EMSO, centered on a joint EMSO cell (JEMSOC), and options for coordinating authority across components (discussed in a later section).
It introduced electromagnetic battle management as the function that monitors, assesses, plans, and directs JEMSO in real time.
It adopted the new "electromagnetic" terminology for EW and its divisions.

The services aligned their own doctrine after the joint publication. The Air Force, for example, redesignated its EW and EMSO doctrine from AFDP 3-51 to AFDP 3-85 to match the joint numbering. The Army's 2021 revision of FM 3-12 carried the title Cyberspace Operations and Electromagnetic Warfare, replacing the 2017 version that used "electronic warfare" in its title.

Why "electromagnetic" replaced "electronic"

The change from electronic warfare to electromagnetic warfare sounds cosmetic, and in part it is. The functions, the acronyms, and most of the definitions survived. The argument for the change is that "electronic" describes the equipment, while "electromagnetic" describes the medium in which the fight happens. Directed energy, infrared and optical systems, and the spectrum as a whole sit more naturally under the broader term. It also aligns the vocabulary of EW with the spectrum-wide framing of EMSO: electromagnetic attack, electromagnetic protection, and electromagnetic support all live inside electromagnetic spectrum operations.

In practice, the older terms persist in unit names, system names, contract titles, older publications, and in the way many practitioners talk. The Air Force's 53rd Electronic Warfare Group, for example, kept its name when it moved under a new wing in 2021. When reading older documents, treat "electronic attack," "electronic protection," and "electronic warfare support" as the predecessors of today's EA, EP, and ES. When writing new material, use the current terms.

The 2020 EMS Superiority Strategy and its implementation plan

In October 2020, DoD released its Electromagnetic Spectrum Superiority Strategy. It replaced the separate spectrum and EW strategies with a single document covering the whole mission area. The public version set five goals:

Develop superior EMS capabilities.
Evolve to an agile, fully integrated EMS infrastructure.
Pursue total force EMS readiness.
Secure enduring partnerships for EMS advantage.
Establish effective EMS governance.

The strategy stated that U.S. dominance across the domains and the spectrum was being challenged by peer and near-peer adversaries. It also leaned on technology themes that recur throughout the mission area: dynamic spectrum sharing, frequency agility, modular and software-defined systems, and less dependence on platform-specific solutions.

The strategy called for an implementation plan within 180 days, which put the target at roughly March 2021. The plan arrived later. Secretary of Defense Lloyd Austin signed it on 15 July 2021, and it was announced the following month. The plan itself is classified. What the department said about it publicly includes the following:

Oversight of implementation would move from the Vice Chairman of the Joint Chiefs of Staff, who had led the effort through an Electromagnetic Spectrum Operations Cross-Functional Team, to the DoD Chief Information Officer in the fall of 2021.
U.S. Strategic Command would serve as the operational advocate for EMSO across the joint force.
A new joint EMSO center under STRATCOM would evaluate, assess, and certify joint EMSO readiness.
The Defense Information Systems Agency (DISA) would act as program manager for a joint electromagnetic battle management capability, with STRATCOM as the operational manager.
The plan included capability planning guidance meant to drive investment priorities and department-wide coordination on technology.

Officials described the plan as the first unified department-level approach to EW and spectrum operations.

What Congress put into law

Congress has repeatedly legislated in this area, and the result is now a cluster of provisions in Title 10 of the U.S. Code, sections 500a through 500f. Among other things, these provisions:

Require the Secretary of Defense to establish processes and procedures to develop, integrate, and enhance the EMSO mission area, with integrated department-wide strategy, planning, and budgeting.
Require annual reporting on the department's EMS strategy and on EMS acquisition programs and research efforts for fiscal years 2025 through 2029.
Task an Electromagnetic Spectrum Operations Executive Committee with assessing whether budget requests fund EMS development adequately, explicitly including development of an electromagnetic battle management capability for JEMSO.
Establish an EMS enterprise operational lead for JEMSO at U.S. Strategic Command, added by the FY2024 National Defense Authorization Act, with annual briefings to Congress on progress toward full operational capability, combatant command readiness, and gaps in evaluating dynamic spectrum sharing.

Spectrum management and electromagnetic warfare: same spectrum, different jobs

The EMSO concept joins spectrum management and EW, but it does not erase the differences between them. They have different purposes, different legal and policy frameworks, and different workforces. Planners who understand both sides can avoid most of the friction that shows up in exercises.

Aspect	Spectrum management	Electromagnetic warfare
Primary purpose	Enable friendly spectrum use without harmful interference	Gain advantage by exploiting, attacking, and protecting in the spectrum
Typical outputs	Frequency assignments, allotment plans, host nation coordination, interference resolution, JRFL inputs	EA target lists and timing, ES tasking and reporting, EP measures, EW reprogramming
Governing framework	National and international spectrum regulation (NTIA for federal users in the U.S., host nation authorities and international agreements abroad) plus DoD policy	Operational authorities from the joint force commander, rules of engagement, and coordination with intelligence authorities for ES
Traditional staff home	J-6 / S-6 communications sections	J-3 / S-3 operations, EW cells, or cyber and EW sections
Main risk if neglected	Friendly fratricide in the spectrum, denied host nation access, systems that cannot be used where they are deployed	Loss of initiative to an adversary that controls the spectrum, exposed friendly emitters

The interaction points are where most problems arise. A friendly EA mission can jam friendly communications if the JRFL is incomplete or not respected. Friendly emitters that are poorly managed create signatures that adversary ES can locate and target. Spectrum managers working peacetime assignment processes may not have the tools or authorities to support a fast-moving fight, while EW planners may not understand the regulatory constraints that limit what can be transmitted in training or in a host nation. JEMSO is meant to put those decisions in one process under one commander.

Organizing the joint force: JEMSO cells, JEMSOC, and the JEC

Doctrine and strategy matter little without staff structures that can actually plan and direct EMSO. Joint doctrine and recent organizational changes address this at two levels: within a joint force headquarters, and at the enterprise level.

Inside a joint force headquarters

JP 3-85 describes a joint electromagnetic spectrum operations cell, abbreviated JEMSOC and commonly called a JEMSO cell, as the staff organization that plans, coordinates, and assesses JEMSO for the joint force commander. In the older model, a joint force might have had a joint EW cell in operations and a joint spectrum management element in communications. The JEMSO cell combines those functions. Publicly available descriptions of JEMSO cell work include:

Collecting information on friendly and adversary emitters, active frequencies, and EW threats, drawing on intelligence reporting and spectrum monitoring.
Analyzing communications, radar, and EW requirements and maintaining the JRFL as a living product.
Deconflicting frequencies across components to prevent friendly interference.
Integrating EA, EP, and ES into the commander's plan and targeting process.
Reporting EMS status to the commander and to assessment staffs.
Building spectrum contingency plans for degraded or denied conditions.

Doctrine also provides for an EMS coordinating authority, a role the joint force commander can assign so that one official coordinates spectrum activities across components day to day. Training material based on JP 3-85 describes combatant commanders and joint force commanders establishing a JEMSOC to support planning, coordination, and control of the spectrum, with the JEMSOC director typically serving as that coordinating authority. The details of how a given command structures these elements vary with the operation and the commander's choices, and the most specific guidance sits in the full doctrine and in classified plans.

The Joint Electromagnetic Spectrum Operations Center

At the enterprise level, the implementation plan's call for a STRATCOM-led center produced the Joint Electromagnetic Spectrum Operations Center (JEC). STRATCOM began standing it up in 2021 and formally established it in July 2023, with its headquarters at Offutt Air Force Base, Nebraska. At establishment, the JEC brought together:

The JEC headquarters at STRATCOM.
The Joint Electromagnetic Warfare Center at Joint Base San Antonio-Lackland, Texas.
A Joint Center for Electromagnetic Readiness at Nellis Air Force Base, Nevada.

The JEC's stated mission is to raise joint force readiness in the spectrum by providing operational leadership, assessing readiness, and standardizing EMSO cells across the combatant commands. Its first commander, then-Brig. Gen. AnnMarie Anthony, said it reached initial operating capability in summer 2023 and expected full operating capability in fiscal 2025. Whether it reached that milestone on schedule, and what readiness assessments it has produced, are not detailed in the public record. Those assessments are largely classified.

Electromagnetic battle management

Electromagnetic battle management (EMBM) is the dynamic monitoring, assessing, planning, and directing of JEMSO in support of the commander's scheme of maneuver. Put simply, it is the function that lets a commander see what is happening in the spectrum, decide what to do about it, and push those decisions to the forces fast enough to matter.

Why it is hard

Traditional spectrum management works on timelines of days to months. Frequency requests go through approval chains, assignments go into databases, and plans get published. EW planning in the targeting cycle often runs on the air tasking order cycle or similar. Neither is fast enough when an adversary is changing frequencies, moving jammers, and hunting friendly emitters in minutes. EMBM is the attempt to close that gap with:

A shared EMS common operating picture fusing friendly emitter data, sensed spectrum activity, intelligence on adversary systems, and environmental effects.
Decision support for courses of action, such as which frequencies to move to, which emitters to silence, and which threats to attack.
Machine-to-machine data exchange with service EW planning tools and, eventually, with the systems themselves.
Integration with broader joint command and control efforts, including Joint All-Domain Command and Control.

Each of those depends on data the department has historically kept in separate systems, at different classification levels, in formats that do not interoperate. GAO's 2024 review of spectrum IT listed the DoD systems in this space, including the Global Electromagnetic Spectrum Information System (GEMSIS), the Joint Spectrum Data Repository, Spectrum XXI, the End-to-End Supportability System, Joint Spectrum Interference Resolution Online, and an EMBM tool, among others. Spectrum XXI is used across the government. GAO noted that DoD had contracted for an analysis of its spectrum IT, planned to migrate systems to the cloud, and had paused modifications to Spectrum XXI during that migration.

EMBM-Joint

The joint program is Electromagnetic Battle Management-Joint (EMBM-J), with DISA as developer and STRATCOM as the operational partner. DISA released a first minimum viable capability in December 2023. As publicly described, it is a cloud-based application giving combatant commands and joint task force JEMSO cells a unified visual display of the EMS battlespace, using a common data layer intended to interoperate with service tools such as the Army's Electromagnetic Warfare Planning and Management Tool. DISA's spectrum program executive office described it as a way to give commanders a visualized EMS common operating picture so they can act quickly.

In April 2024, DISA awarded Palantir a 12-month, $9.8 million agreement to prototype an EMBM-J decision support capability at Impact Level 6, focused on mission analysis, course of action development, wargaming, and product generation. The pattern, a minimum viable product followed by incremental capability releases and a separate decision support prototype, is typical of current software acquisition approaches.

What is not public is how well EMBM-J performs in exercises, how many commands use it operationally, or how much of the planned functionality has been delivered.

How the services organize for EMSO

Each service organizes, trains, and equips its own EMSO forces, and their approaches reflect different histories and missions. The descriptions below cover what is publicly documented. Force structure numbers and specific capability details are often not published.

Army

The Army largely divested its tactical EW capacity after the Cold War and spent the years in Iraq and Afghanistan focused on countering radio-controlled IEDs. It has been rebuilding since. EW officers and soldiers now sit in the Army's cyber branch, and the service uses the label cyberspace electromagnetic activities (CEMA) for the staff function that integrates cyber operations, EW, and spectrum management. CEMA sections at brigade and higher bring together EW personnel and spectrum managers, the latter drawn from the signal community.

Key public elements include:

Terrestrial Layer System (TLS): a family of integrated SIGINT, EW, and cyber systems. The TLS Brigade Combat Team Manpack reached first unit issue in summer 2024 after a compressed middle-tier acquisition effort. The Army describes it as capable of radio frequency survey, signals collection, direction finding, and EA, with plans to field it across brigade combat teams over roughly three years.
11th Cyber Battalion: activated in 2022, it provides expeditionary CEMA teams that can be attached to supported units for radio-frequency-enabled cyber effects, EW, and related operations. Army leaders have discussed extending similar capability to division level.
Doctrine: FM 3-12 covers cyberspace operations and EW, and the Army has aligned its terminology with JP 3-85.

Navy

The Navy has the longest continuous investment in airborne and shipboard EW among the services. Its EMSO forces include:

EA-18G Growler squadrons: the joint force's primary carrier-capable airborne EA platform. The Next Generation Jammer Mid-Band pod, which replaces the decades-old ALQ-99 jamming pod in its band, reached initial operational capability in December 2024. The Next Generation Jammer program, developed cooperatively with the Royal Australian Air Force, is structured around separate pods covering different frequency ranges.
Shipboard EW: surface ships carry ES and EA systems for self-defense against anti-ship missiles and for situational awareness. The Surface Electronic Warfare Improvement Program has upgraded these systems in blocks over many years.
Information warfare community: the Navy groups EW, cryptology, intelligence, communications, and related specialties under its information warfare community, with Naval Information Forces serving as the type commander responsible for manning, training, and equipping those forces.

Air Force

The Air Force made the most visible organizational move after the 2020 strategy. On 25 June 2021, Air Combat Command activated the 350th Spectrum Warfare Wing, initially at Eglin Air Force Base, Florida, pending a permanent basing decision. The wing was created to address atrophy in EW expertise and to give the service a single organization focused on EMS capability for the combat air forces. Its first commander, Col. William Young, said at activation that if the force loses the fight in the EMS, it will lose the fights in all other domains.

The wing's core missions include EW reprogramming and mission data, the work of updating threat libraries and system software so that aircraft EW systems and sensors recognize and respond correctly to the emitters they will face. That work matters for every modern combat aircraft, including the F-35, whose mission data files tell its sensors what they are seeing. The 53rd Electronic Warfare Group (a unit name that predates the terminology change) moved from the 53rd Wing into the new wing. Its subordinate structure includes spectrum warfare groups, with the 350th and 850th Spectrum Warfare Groups activated with the wing and a 950th Spectrum Warfare Group added in 2024.

Beyond the wing, Air Force EMSO capabilities include the EC-37B Compass Call, which is replacing the EC-130H as the service's airborne communications EA platform, self-protection EW suites on combat aircraft, and ES contributions from ISR platforms. The Air Force redesignated its EMSO doctrine as AFDP 3-85 to match the joint publication.

Marine Corps

The Marine Corps retired its EA-6B Prowlers in 2019, ending its dedicated tactical jamming aircraft, and shifted toward a distributed approach built on its information warfare organizations and on EW payloads carried by multiple platforms. Key public elements include:

MEF Information Groups (MIGs): in July 2017, the Marine Corps began converting its MEF headquarters groups into MIGs, starting with I MEF at Camp Pendleton. Each MIG brings together the MEF's radio battalion, intelligence battalion, communications battalion, ANGLICO, and related units. The stated purpose was to keep the MEF commander informed on the security of command and control networks and on EMS and cyberspace operations and vulnerabilities, and to deliver EW and cyber capability to the force.
EMSO cells within the MIG: public reporting describes an Information Command Center at each MIG that includes an Electromagnetic Spectrum Operations Cell responsible for coordinating EMS operations and EW for the MEF.
Radio battalions: these provide SIGINT and EW Marines. Under Force Design, Marine Corps officials have described assigning SIGINT and EW Marines down to infantry companies, with SIGINT/EW warrant officers at battalion and Marine Littoral Regiment headquarters responsible for EW planning at their level.
Marine Corps Information Command: activated in January 2023 at Fort George G. Meade, Maryland, it brings together the Marine Cryptologic Office, the Marine Corps Information Operations Center, and the Marine Cryptologic Support Battalion to integrate information capabilities across the Fleet Marine Force and with the joint force.
Systems: the ALQ-231 Intrepid Tiger II pod family provides communications EA and ES from aircraft including UH-1Y helicopters, MV-22s, and KC-130Js. Ground systems include high-power vehicle-mounted EA capability and the MAGTF EW family of ground systems, described as including team-portable, vehicle-mounted, backpack, and wearable variants.

Marine officials have emphasized ES as something the Marine Corps can provide to the naval and joint force during competition, not only in conflict. That fits the stand-in force concept, in which small Marine units operating inside an adversary's weapons engagement zone collect and pass information while managing their own signatures carefully. For these units, emission control is a survival requirement. The Corps has continued to adjust its EW organization since Force Design began, and public detail on newer EW-focused organizations is limited.

Current challenges

Governance and implementation

GAO's December 2020 report, GAO-21-64, remains the most comprehensive public assessment of EMS superiority governance. Its main findings were:

DoD had not fully implemented its 2013 or 2017 strategies, largely because it did not assign senior leaders with clear authority or establish oversight processes.
Governance was dispersed across many DoD components with no single accountable official, and senior EMS responsibilities sat at relatively low organizational levels.
DoD had not met statutory requirements to establish processes to integrate EMSO across the department, had not formally proposed governance reforms, had not clearly assigned senior leadership for long-term strategy implementation, and had not established oversight mechanisms such as performance metrics and regular progress reviews.
Additional challenges included outdated capabilities, lengthy acquisition processes, workforce and training deficiencies, and growing spectrum congestion from commercial demand.

GAO made recommendations covering integration processes, governance reform, senior leadership assignment, and oversight and accountability. DoD concurred with some and partially concurred with others, pointing to pending organizational decisions. In March 2021 testimony, GAO's director for defense capabilities and management warned that the United States risks losing control of the battlefield if it does not control the spectrum, and that the 2020 strategy faced the same risk of non-implementation as its predecessors.

Since then, the implementation plan was signed, DoD CIO took over oversight, the JEC was established, and Congress codified an EMSO Executive Committee and an operational lead at STRATCOM. Those steps respond directly to GAO's concerns. Whether they have produced measurable improvement in readiness is harder to judge from public sources, because readiness assessments and the implementation plan's metrics are classified. The statutory annual reporting requirements running through fiscal 2029 are the best indicator that Congress intends to keep asking.

Workforce

Workforce problems show up across nearly every assessment of the mission area. GAO identified insufficient expertise and training deficiencies in 2020. The underlying causes are well known to practitioners:

Two decades focused on counterinsurgency left a gap in experience with high-end EW against a peer adversary.
EW and spectrum management career fields have historically been small, and in some services EW was a secondary specialty or additional duty.
Spectrum managers are trained largely for peacetime assignment processes, while EW personnel are trained largely for tactical effects. JEMSO requires people who understand both.
Realistic training is constrained by regulatory limits on transmitting in the United States, especially for jamming GPS or commercial bands, and by the cost and scheduling demands of open-air ranges.

New organizations such as the 350th Spectrum Warfare Wing, the Army's expanded CEMA force, and the JEC respond to these problems. Public metrics on whether they have closed the gap are not available.

Spectrum sharing pressure

The spectrum DoD needs is also prime commercial real estate. Mid-band frequencies in particular are valuable for 5G and future 6G networks, and several of those bands host important military systems. The policy fight over the lower 3 GHz band (3.1 to 3.45 GHz) illustrates the tension.

The department operates many radar systems in that band, including systems used for missile defense, airborne early warning, air surveillance, and counterfire. Defense officials testified that relocating some of those systems could take decades and cost enormous sums. For one system, the Aegis radar, a DoD official put the cost of replacement at about $120 billion over roughly two decades. DoD's Emerging Mid-Band Radar Spectrum Sharing (EMBRSS) assessment, completed in 2023 and released in redacted form in April 2024, concluded that sharing the lower 3 GHz band was not feasible unless specific conditions were met, including DoD retaining primary use of the band and meeting particular security requirements, with dynamic sharing possible only in a limited form.

Congress addressed the question in the reconciliation law signed on 4 July 2025. That law restored the FCC's general spectrum auction authority through September 2034 and established a pipeline of at least 800 megahertz for commercial auction, with deadlines for NTIA to identify federal spectrum and for the FCC to complete auction tranches. It explicitly excluded the 3.1 to 3.45 GHz band and the 7.4 to 8.4 GHz band, the latter used for military X-band satellite communications, from the bands that could be identified for auction. Those exclusions protect two major DoD equities, but the pipeline still requires substantial federal spectrum to be identified elsewhere, and some of that will come from bands federal users currently occupy.

The process for making those decisions is itself a subject of oversight. In June 2026, GAO reported (GAO-26-107873) that DoD generally follows leading collaboration practices for its internal frequency coordination, and that the EMBRSS working group met most or all aspects of several leading practices. GAO also found that DoD did not clearly tell nonfederal participants whether and how their input would be used in the EMBRSS study, and that DoD and NTIA lacked documented processes for a 2024 study of the 37 GHz band. GAO recommended that DoD CIO document how stakeholder input is evaluated and that DoD and NTIA establish written approaches for future repurposing studies. Both agencies agreed.

The direction in law and policy is more sharing and more dynamic access. Title 10 now requires the STRATCOM operational lead to evaluate tactics and procedures for dynamic spectrum sharing. Systems designed around exclusive access to a fixed band will face growing pressure.

Tools, data, and acquisition

DoD's spectrum IT has accumulated over decades in separate systems, and GAO's 2024 report showed modernization still in the planning stage. Moving data between unclassified spectrum databases and classified threat and EW data remains a practical obstacle for EMBM. GAO has also pointed to long acquisition timelines for EW systems facing threats that change quickly. The Army's middle-tier approach to TLS and DISA's incremental releases of EMBM-J are attempts to shorten that cycle.

What to watch

The EMSO enterprise has a clearer structure than it did in 2020: one joint publication, one strategy, an implementation plan, a designated oversight official, a joint center, a joint battle management program, and statutory reporting requirements. The open questions are about execution. Indicators worth tracking in the public record include:

JEC maturity: whether it publicly confirms full operational capability, and whether congressional briefings under 10 U.S.C. 500e describe measurable readiness improvement at the combatant commands.
EMBM-J delivery: releases beyond the initial minimum viable capability, transition of decision support prototypes into production, and integration with service tools.
Annual EMS reporting: the strategy and program reports required through fiscal 2029, and any GAO follow-up on the recommendations from GAO-21-64.
Spectrum pipeline decisions: NTIA's identification of federal spectrum under the 2025 law, which bands are selected, and what sharing or relocation arrangements DoD accepts.
Service fielding: TLS fielding across Army brigades, Next Generation Jammer progress beyond the mid-band pod, Marine Corps ground and airborne EW fielding, and Air Force reprogramming capacity.
Workforce structures: changes to EW and spectrum management career fields, joint training standards for JEMSO cells, and access to realistic training ranges.

The argument behind EMSO is widely accepted: a joint force that cannot see, use, and control the spectrum will struggle to do anything else. Since 2020 the department has built the doctrine, organizations, and programs to act on it. The public evidence shows real structural progress alongside persistent gaps in workforce, tools, and measurable readiness, with commercial demand for spectrum adding pressure from a different direction.