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As the Trump administration makes a generational change in U.S. grand strategy, it should create a new map of the world that better aligns military activities to that strategy. The current command structure is inefficient and slow—designed for an era when the United States’ military was larger and threats were more easily contained and geographically aligned. As a result, increasing lethality will require more than just cutting the number of general officers and consolidating headquarters. It requires a new framework for seeing the world. It requires a new map.
Making a new map starts with a bureaucratic document unknown to most Americans that has significant consequences for global security architecture: the Unified Command Plan (UCP). Every two years the chairman of the Joint Chiefs of Staff (CJCS) initiates a review of the UCP. Sometimes there are sweeping changes, like creating new functional commands to address cyber and space operations. Other times, the UCP adjusts regional priorities, such as the creation of the U.S. Central Command (USCENTCOM) in 1983 and the U.S. Africa Command (USAFRICOM) in 2007. And proposed reforms—both today and in years past—generate intense debates in Congress and across the Pentagon.
As strategy changes, the map the Pentagon uses to align military power to national security interests should change. The Trump team is correct to call for bold changes to the UCP. In fact, substantial changes have the potential to improve command and control, flexibility, and adaptability for day-to-day competition and war fighting while modestly reducing costs.
Two possible ways to achieve these gains are to
The principal trade-off between these approaches is placing a greater emphasis on border security and day-to-day competition versus prioritizing preparation for global war against a rival great power. That is, should the United States manage its defense commitments by prioritizing a “world of regions” or visualize and describe military strategy using a single map focused on preparing for a global war, most likely with China? This global competition in turn would require mission-focused commands that adapt to the threat across different regions.
If the Trump national security team aims to prioritize addressing immediate threats—through measures such as strengthening border security, using security cooperation to shape strategic conditions, and conducting deterrence operations—it should consolidate the combatant commands (CCMDs) and better align operation, activities, and investments in support of regional competition. This approach focuses on the most likely course of action: day-to-day competition and using military forces to deter adversaries and support partners.
Alternatively, if preparing for protracted, global conflict is more important, it should eliminate regional CCMDs and focus on a single global struggle that requires synchronizing effects across domains. This approach prioritizes the most dangerous course of action and sacrifices gaining access and reassuring partners regionally for a more a direct approach to securing U.S. interests globally through mission-aligned task forces that constantly evolve and adapt. The trade-off is regional nuance for global focus.
While these approaches are not mutually exclusive, the difference is one of prioritization and how best to align authorities, command structures, and the marginal defense dollar. Both of these options reduce the current number of commands, lower the number of four-star officers, and reduce the burden of manning service component headquarters. And any restructuring should focus on improving the efficacy of the command structure to ensure political leaders have access to adaptive and dynamic military options in lieu of cumbersome, and often stale, plans.
Regardless of the path chosen, there are additional steps the Trump national security team could take to support improved flexibility and adaptability. Most importantly, the team should add two deputy secretaries of defense (DSDs) for current and future operations who have command authority over sections of the department. This will make the Department of Defense (DOD) more agile by allowing faster decisions for current and future operations, essentially enabling greater decentralized execution, which is necessary for large bureaucracies. This simple change also reserves the defense secretary’s time for the thorniest, most strategic issue: determining when to sacrifice the future for the present, or vice versa. This added bureaucratic layer is only helpful if the DSDs have decisionmaking authority. They must be in the chain of command.
The U.S. military has an extremely broad range of global responsibilities across many functions, which creates demands for the secretary to lead an organization larger than several small countries. This reality means the secretary should push many day-to-day decisions to lower levels so he can focus on the long-term strategic issues and one or two immediate priorities. Placing DSDs in the chain of command with some budgetary control creates a structure to facilitate lower-level decisions for many issues. The current limited number of civilians in the U.S. chain of command—numbering just one or two for the military services—is offset by numerous, equivalent four-star military commanders and over 40 four-star officers, which President Donald Trump and Congress should reduce. Consolidating several combatant commands in either of the ways this report describes offers potential savings. After all, three-star generals lead the militaries of several small countries.
Although the authors firmly believe these changes will improve the effectiveness, agility, and efficiency of the DOD, the department needs to quickly conduct additional classified analysis and war gaming with congressional staff to ensure the production of a new UCP and National Defense Authorization Act within a year to codify these revolutionary adjustments.
This report proceeds by providing an overview of the UCP’s history and reform debates. It then provides two options for substantially reforming the UCP. The report concludes by listing major recommendations the Trump administration should consider regardless of the path it takes to redraw its military map of global competition.
The Pentagon’s military map of world is the UCP. President Harry S. Truman approved the first UCP in 1946—then known as the Outline Command Plan. The original plan called for a Far East Command (FECOM) for Japanese occupation, along with a Pacific Command (PACOM), Alaskan Command, Northeast Command, U.S. Atlantic Fleet (later Atlantic Command, or LANTCOM), Caribbean Command, and European Command (EUCOM). From the beginning, drawing lines to focus military operations on a global scale led to service conflict. In the early years, this conflict centered on whether to place the Mariana Islands and Bonin under PACOM or FECOM, a fight largely defined by rival service perspectives between the U.S. Navy and U.S. Army. This trend continued over the decades and included failed efforts by the U.S. Army to raise the status of Military Assistance Command Vietnam to a unified command supported by PACOM.
As a map, the UCP addressed not just physical boundaries but complex coordination questions involving emerging military capabilities. Control over strategic forces—from nuclear weapons to space and cyber capabilities—has long plagued planners. As early as 1946, Army Air Force officers advocated for a Strategic Air Command (SAC) operating globally, seeing the alignment as reflecting the principles of mass and unity of command as well as hard lessons learned in World War II. This premise was subsequently challenged by the U.S. Navy, which argued that ballistic missile subs must work alongside other ships, leaving them subordinate to fleets in LANTCOM, EUCOM, and PACOM. The debate came to a head in 1960 when the secretary of defense gave the commander-in-chief, Strategic Air Command (CINCSAC), the director, Strategic Target Planning a U.S. Navy deputy rather than creating a unified command.
Similar debates defined the emergence of space and cyberspace as war-fighting domains, with a mix of defense analysts and Congress alongside military members trying to align emerging technologies with their war plans and service priorities. Command structures to manage operations in space evolved within the U.S. Air Force between the 1960s and the creation of Space Command in 1985. The command emerged in parallel with President Ronald Reagan’s Strategic Defense Initiative. The command was officially closed in 2002, with space missions transferred back to the U.S. Strategic Command (USSTRATCOM) until Congress approved a measure to reestablish it in 2018.
Interest in separate military capabilities aligned to cyber missions emerged from the fallout of a war game. Eligible Receiver 97—an early cyber-focused exercise—created deep concerns about systematic vulnerability in the DOD, leading to the creation of the Joint Task Force Computer Network Defense (JTF-CND) in 1998. The entity evolved into a JTF working for the U.S. Space Command (USSPACECOM) until it transitioned to USSTRATCOM in 2002. In 2009, then–Defense Secretary Robert Gates directed the reorganization of service cyber forces, including merging two separate cyber task forces to form the U.S. Cyber Command (USCYBERCOM).
This history provides crucial context for thinking about reforming the UCP. Historically, changing trends—from the emergence of space as a war-fighting domain to the invention of cyberspace—and shifting regional threat dynamics have pushed defense officials to rewrite the UCP and create new maps of how best to align military power with strategic interests. The United States stands at the cusp of a similar moment in 2025. As a result, the DOD should consider sweeping changes to the UCP to streamline day-to-day competition and war-fighting activities while modestly reducing costs. While this report discusses two options for consolidation, the administration could also consider a third option: mission-oriented CCMDs, building on the work that think tank Center for Naval Analyses (CNA) completed in 2024 and provided to Congress and the National Security Council. Fewer CCMDs with appropriate authorities give combatant commanders (CCDRs) the ability to streamline decisionmaking and move resources between priorities as requirements shift.
Given its division of the world into neat lines and attempts to synchronize multiple domains, the UCP has historically been a lightning rod for defense debates. Most of these involve disputes about territory, forces, and freedom of action (i.e., authorities as well as command and control). Substantial adjustments to the UCP have the potential to improve effectiveness and reduce costs if carefully considered.
The first debate centers on whether the military should organize its force around geographic regions (i.e., territory) or functional missions and capabilities (i.e., force) lines. This relates directly to strategy, force posture, unity of effort, and operational art, as it impacts how military formations are organized, commanded, deployed, and employed across theaters. Within this debate is a second order question of whether to organize forces around one, global fight or a series of flexible regional contingencies. At one extreme, forces resemble the McNamara-era efforts to establish a unified command over all general-purpose forces in the United States focused on joint training, experimentation, and mobilization exercises. At the other extreme is a base force construct built around regionally aligned formations or even a world of a single global wartime commander.
A second debate concerns practical questions: How large and broad should each command be? Where should the lines be drawn functionally and geographically? The larger the command, the more flexibility the commander has to shift resources between the different responsibilities owned by the command. However, this also means the commander has less time to focus on important but often less urgent issues. If a commander is responsible for fewer countries or functions, they have space for more subject matter expertise but will also need to make tough prioritization decisions or recommendations when trade-offs are necessary. There is ongoing tension between CCMDs having a clear focus versus flexibility to respond to global challenges that cross traditional geographic boundaries and domains. For example, is it better to have separate space and strategic commands or one, merged entity? Over time, this tension has emphasized a clear but relatively narrow focus, leading to functionally and geographically aligned commands that struggle to support global campaigning and are top heavy—led by four-star commanders.
This question of command arrangements becomes more central with the emergence of joint all-domain operations and global campaigning. Today, war against another great power will cross all functional commands and many, if not most, regional combatant commands. In this world, there are likely advantages to fighting as a single combatant command using a single joint task force with one combined joint air force component and land component. There are different advantages to using a series of small, subunified commands and task forces with flexible authorities and shifting areas of operation. The concept of subunified commands has been used, for example, to support global cyber operations as well as to focus on specific mission areas like the Combined Joint Task Force–Horn of Africa. According to a Government Accountability Office study, historically combatant commands have relied on subordinate commands for mission management and execution, leaving one to wonder if a series of more adaptable joint interagency task forces, led by ranks as low as colonels to as high as four-star generals, might perform as well or better than CCMDs in combat.
This report proposes two UCP reform options: (1) modest consolidation of the current CCMDs, retaining a focus on theater shaping and deterrence, or (2) eliminating regional CCMDs to improve lower-level coordination between fighting elements during war. The principal trade-off is the level of emphasis on border security and day-to-day competition relative to preparing for war with a great power. While day-to-day competition focuses on deterrence and has links to war plans through nested competition activities, the relationship is at best indirect and often difficult to measure and assess. A more direct focus on war fighting would reduce the emphasis on day-to-day competition and security cooperation. In practice, this would mean fewer partner exercises and more time spent rehearsing aspects of major plans and experimenting with emerging capabilities. Regardless of which option the Trump team pursues, the DOD would benefit from additional bureaucratic reforms to make the Office of the Secretary of Defense (OSD) more agile, including by creating additional DSDs with command authority over CCMDs and the military services.
CCMD Consolidation
Consolidating CCMDs runs contrary to the United States’ recent history of creating more CCMDs to ensure every important issue has the strongest advocate. However, these expansions effectively created grade inflation—too many issues require a four-star advocate and resolution requires the secretary of defense or president, the only individuals authorized to resolve disputes between CCDRs or task CCMDs. Thankfully, the DOD can do many things with consensus; however, consensus is rare when making trade-off decisions. Reducing the number of CCMDs has the potential to modestly reduce DOD costs and, with appropriate changes in authorities, significantly improve operational and strategic efficiencies.
Merging several CCMDs will not change the importance of each region and could recreate the past problems that drove CCMD proliferation. Therefore, consolidating CCMDs must coincide with substantial changes to authorities and culture to avoid past problems. Each CCDR needs the ability to shift resources between the problems their CCMD is responsible for, and leadership must accept that CCMDs cannot solve every problem. Reasonable consolidation could turn the current 11 CCMDs into 6, which should reduce the number of decisions the secretary needs to make and streamline meetings for the secretary and chairman of the Joint Chiefs of Staff. It also would streamline key forums like the “tank”—Joint Chiefs of Staff meetings—which often include 11 combatant commanders, 6 service chiefs, the CJCS, the vice chairman, and many of the Joint Staff’s three-star principals (e.g., J2, J3, J5). The large number of senior leaders in each meeting often limits meaningful discussion, as time is needed to give every leader an opportunity to comment.
These changes assume that consolidation can drive prioritization and integration. Larger geographic areas allow regional-oriented CCMDs to better manage assigned forces and engage partners. This regional perspective better aligns with campaigning and the use of operations, activities, and investments to deter adversaries and reassure partners. This will not significantly reduce the workforce because the CCMD will still need experts for all the issues.
Consolidated, functionally oriented commands provide a way to compete in space and cyberspace, as well as to conduct deterrence operations in a synchronized manner. Campaign-related activities in space can be integrated with ongoing cyber campaigns to better deter or encourage specific adversary actions. The current authorities required to conduct space and cyberspace operations can be delegated to three-star commanders reporting directly to the four-star commander of STRATCOM. An alternative would be to keep nuclear-related capabilities separate and distinct but merge cyber and space capabilities. The question again is one of emphasis and prioritization, and is only answerable by the president given his understanding of security and how best to align military capabilities to advance his grand strategy.
Making this aggregated structure work requires appropriate delegation to empowered deputies. Each region or function needs a three-star deputy CCDR with the authority to direct activities within their area of responsibility. Without command authority, consolidation provides limited operational benefit. Overall, this structure supports the mission command and decentralized execution that senior military leaders routinely advocate for. Delegating most authorities and responsibilities frees the CCDR to focus on issues affecting all subordinate elements, set strategic priorities, and resolve trade-offs. The CCDR can, and should, withdraw authority when the strategic environment dictates. Three-star generals have sufficient experience and gravitas to provide command and control of daily activities for competition, lead war planning, and manage most other tasks. The military only promotes individuals to three-star general if they have the ability to manage a large organization. Four-star generals have the skills and experience for a broader focus.
In practice, this approach has worked before—for example, when the EUCOM commander was responsible for Africa, Israel, and Europe. The commander quickly and efficiently adjusted headquarters efforts between these regions as the situation warranted. Prior to the 2006 Israel-Lebanon conflict, the EUCOM staff and the commander focused heavily on North Africa, which had the most prominent threats at the time. However, when the Israel-Lebanon conflict broke out, commander and staff time shifted rapidly to the conflict. Once the conflict ended, there were fewer priorities, operations, and CCMD decisions related to EUCOM’s responsibilities in its narrow slice of the Middle East. As a result, EUCOM resources and attention shifted quickly back to North Africa. Ironically, when AFRICOM stood up, many of the North Africa experts at EUCOM stayed in EUCOM because those experts occupied billets allocated for Middle East responsibilities. A similar reaction occurred when there was a substantial counterterrorism threat in Germany.
Consolidating the National Security Agency and the Cyber, Space, and Strategic Commands will cause consternation, given that they were recently separated (in 2010 and 2019). However, that was before Space Force existed, and consolidation assumes empowering three-star leaders for each of these organizations. All of these organizations have significant interdependencies and exist in highly compartmented environments, which makes evaluating consolidation a complex but worthy task for official channels. These 3–4 missions remain paramount for the future and current fight—after all, CYBERCOM is fighting an active war every day—but U.S. three-star generals have incredible talent and can manage these issues. The United States appears to have made these commands four-star positions to emphasize their importance and improve their bureaucratic influence in an inflated bureaucracy.
While consolidation has the potential to allow faster decisions and adaptation to changing situations, Transportation Command (TRANSCOM) needs to remain independent. Few outside the military understand TRANSCOM’s importance because its mission is viewed by too many as boring and technocratic. However, TRANSCOM punches well above its weight; the old adage that “amateurs talk tactics, professionals talk logistics” remains true. TRANSCOM provides the professionals and clear technical advice necessary for every CCMD, Joint Staff, and secretary. Having observed many conversations about war preparations, the DOD needs a command to objectively articulate the concrete logistical trade-offs for prioritization decisions between CCMDs. Most combatant commands make value judgments based on strategy and their priorities. TRANSCOM provides the hard math regardless of the value judgment, which is probably why it houses the Joint Enabling Capabilities Command that supports every CCMD when crises strike, from nuclear plant disasters (Fukushima, Japan) to military invasions (Russia-Ukraine) to hurricanes (Katrina) to counterterrorism (Iraq). Outside professional military circles, few understand TRANSCOM, but it is a vital CCMD for managing logistics and sustainment support, as the DOD learned through the Nifty Nugget exercise in 1978. These competing interests have not changed since then.
Special Operations Command (SOCOM) would largely remain as is, with responsibility and authorities for global Special Operations Forces (SOF) activities and service-like responsibilities (e.g., procuring SOF-specific equipment). SOCOM would continue to work with the Joint Staff and CCMDs to ensure SOF activities advance peace-time objectives, set conditions for successful war fighting, defeat counterterrorism threats, and generally support global priorities effectively. In some cases, SOF capabilities will support lower priorities when those capabilities lack efficacy against higher priorities. Coordination with CCMDs and embassies will remain crucial to prevent conflict with other U.S. activities.
The primary advantage of consolidation, beyond headquarter reductions, is allowing CCMDs to prioritize resources against threats within their responsibility according to strategic guidance from the secretary and president. Consolidation will reduce the need for decisions by the secretary and president and free them to focus on grand strategy and global issues. This should not affect crisis response, where SecDef or POTUS will pull specific decisions up to their level—a normal and sensible reaction.
An important consolidation risk is the potential to deprioritize important tasks. Every CCMD has significant responsibilities. However, U.S. three-star generals are eminently capable of commanding large organizations if given sufficient authorities. Streamlining requires cuts somewhere. The greatest consolidation risk is even slower decisionmaking, which could occur if four-star commanders retain this authority for everything and their three-star deputies become another bureaucratic layer to traverse. Empowering three-star deputy commanders with the default authority to make all decisions except those narrowly, and explicitly, reserved to the CCDR provides the best chance to minimize this risk. Additionally, replacing four-star commands with three-star ones reduces the number of support staff and helps flatten organizational structures.
Global Combatant Commands
Although consolidation could improve command and control, CCMD responsibilities are based on historical threats and technologies. Twenty-first century threats are global and do not conform to UCP boundaries. From great powers to violent extremist organizations (VEOs), threats have access to weapons and means that allow them to exploit the gaps and seams created by the current joint command arrangements. All command and control arrangements are designed to optimize the military’s ability to accomplish tasks in the most efficient and effective manner possible. Rather than optimizing for efficiency or effectiveness, the current UCP construct limits operational commanders’ ability to exploit what their units can do while forcing the secretary of defense to make tactical level deconfliction and deployment decisions. If an enemy commander responsible for the Eastern Mediterranean imposed the current boundaries on the DOD, he would receive a medal for forcing U.S. tactical commanders to coordinate between three CCMDs before acting. The current system has too many exploitable seams that U.S. adversaries actively exploit.
The United States funds its military to fight a single major theater war at a time, but has eight theater-level headquarters, including Korea and NATO. Because of the current and projected size of the military, the United States only needs a single, dedicated four-star Operational Level command (OPCOM) to employ forces globally against an adversary. This would prevent adversaries from exploiting the seams between CCMDs, allow streamlined operational decisions, and reduce costly force structure. In this “task based” approach, all remaining four-star commanders have global “functional,” rather than regional, responsibilities. Although regional commands remain necessary, they would have narrow authority and be limited to two- or three-star peacetime “shaping” and “competition” commands that support all four-star commands as directed.
These smaller regional commands would lose combatant command authority (COCOM) but would tactically employ forces provided by the Services and four-star commanders. The regional commands would have no permanently assigned forces or obligation to monitor or coordinate operational fires, maneuver and effects, etc. Using a portion of the force structure savings, the DOD would activate a four-star level Operational Level Warfighting Command, or OPCOM, in the United States to exercise command authority over any forces deployed outside the country for combat. OPCOM would be the only four-star command with the full suite of joint subordinate commands—such as a joint land component, joint maritime component, and joint air component—allowing for further cost and structure savings. The Pentagon would only employ geographic UCP boundaries with two- or three-star coordinators to meet peacetime “conditions setting” requirements; geographic UCP boundaries would have no bearing on OPCOM’s ability to employ forces or assign priorities. Regional commands consistently ask for any force available, regardless of the national strategy. Reducing the rank of regional commanders will make it easier for the Pentagon to make decisions based on long-term strategy instead of immediate, but rarely vital, crises. Four-star commanders have significantly greater ability to push the system to ignore strategic priorities for immediate demands because only an extremely busy secretary or even busier president have the authority to overrule a CCDR.
An OPCOM structure will operate differently than current command constructs. In a war with the People’s Republic of China (PRC) or Russia today, U.S. forces would have difficulty attacking Russian or PRC extended lines of communication along the “Belt and Road” countries because multiple CCMDs must deconflict forces and effects. This friction may be acceptable against opponents who cannot operate with advantage in all domains, but would likely cause the United States to lose a war with the PRC or Russia. A single OPCOM would be better positioned to conduct war planning; for example, the operational design and operational art tasks of choosing where and how to use forces without bias for or against any specific region. Today’s CCMDs have an incentive to prioritize their area of responsibility first—only the Pentagon (OSD, Services, and Joint Staff) really look at the world holistically. Additionally, OPCOM’s limited responsibilities for day-to-day competition activities would allow greater focus on preparing to conduct combined, joint all-domain conflict under the toughest conditions. Today, immediate competition requirements often, and appropriately, pull the focus of CCMDs from the important but longer-term war-planning and preparation activities.
This OPCOM construct would likely require another nation to fulfill the four-star Supreme Allied Commander Europe role that the EUCOM commander holds today. While it would be difficult, it would not be impossible to reassume the role during a major theater war if a NATO nation were attacked.
Moving to lesser threats, a three-star Joint Task Force (JFT) could likely handle most situations. A JTF built around the 5th Fleet could likely handle a conflict with Iran given Iran’s lack of global capabilities. Similarly, a three-star JTF supporting South Korea’s armed forces should be sufficient until the PRC or Russia become significantly involved, which OPCOM could address. Special Operations Command has sufficient capabilities to deal with the long-term and acute threats from violent extremist organizations while existing O6-O9 tactical headquarters could form the core of a JTF to handle other unforeseen contingencies short of a great power conflict.
In addition to streamlined command and control, the OPCOM approach’s primary advantage is improved resilience. Moving operational command and control to the United States would fully leverage the nuclear shield against long-range strikes and provide the National Command Authority additional distance to determine the extent of a U.S. commitment with less concern for U.S. forces in immediate contact with a threat. These changes would also free senior leadership to focus on strategy and not referee CCMD requests for forces and reclamas. Additionally, this would reduce requirements for service component commands because there would be less need for regional combatant commanders to receive advice on service force employment.
Ultimately, the major benefit is a single command focused on fighting a global war. A single command would, by definition, be better placed to fight the way emerging joint concepts, including the Joint Warfighting Concept and Joint All-Domain Operations, imagine. This command could rapidly synchronize pulse attacks across domains and, given longer weapons ranges and space and cyber effects that are less fixed to terrestrial geography, quickly shift priorities. The command could better align smaller JTFs dynamically stood up to seize local opportunities, for example targeting People’s Liberation Army (PLA) terrestrial space assets outside of China like downlink stations and space ports, and manage a global blockade designed to limit the flow of resources to Beijing.
There are disadvantages to this proposal as well. Reducing the role of the regional commanders would likely create perception of regional disinterest since the change would be perceived and portrayed as a retreat back to “Fortress America.” Maintaining the subject matter experts in the middle ranks (military and civilian) should limit the loss of regional expertise. Such a move would also require a substantial culture change in the U.S. military, which has operated with the current model since the 1980s—a period longer than the careers of nearly all serving military officers. A final challenge would be blending the new structure into existing alliance relationships such as Europe and South Korea, where the U.S. regional commander holds a coalition leadership role. However, this last challenge also provides a potential opportunity if the United States wants to lower its costs for supporting international alliances.
Aligning the National Security Enterprise
Alongside fundamental changes to the UCP, reorganizing the OSD without growing the overall staff size could address concerns CCDRs, their staffs, and the National Security Council frequently raise about slow DOD decisionmaking. Currently, approximately 16 individuals report directly to the secretary and 19 individuals report directly to the sole deputy secretary. Importantly, the secretary must approve any dispute between CCDRs, even over a single military dog team. The secretary’s span of control is far too large, which forces him to make too many decisions and creates an unacceptably slow decisionmaking process. Providing the secretary with three empowered deputy secretaries, in the chain of command, provides the best way to mitigate this problem.
Note: The chart shows a potential DOD organization structure without additional deputy secretaries and streamlined to six combatant commands. In this structure, all conflicts between combatant commanders or service secretaries require secretary involvement.
Note: The chart shows a potential DOD organization structure with deputy secretaries and six combatant commands. The secretary only needs to resolve conflict between services and combatant commands or around issues over which he chooses to retain all decisionmaking authority.
The current OSD staff capacity can produce far more decision memos than the secretary can review and act upon. For example, the secretary ordered a CCMD to make an adjustment in a meeting coordinated and attended by the office of one of this report’s authors. However, the CCMD staff refused to follow the secretary’s clear verbal guidance to their commander and the OSD staff until they received official written guidance from the secretary himself to “prevent miscommunication,” which wasted several weeks and hundreds of staff hours. Having deputy secretaries who can task service secretaries, CCDRs, and agency heads would substantially mitigate this problem.
One DSD could be responsible for current operations and make decisions when CCMDs disagree. A DSD for future operations could lead the services to manage trade-offs between services while overseeing service manning, training, and equipping functions. Service needs and CCMD needs would still come into conflict, but the two DSDs would be able to consolidate current and future issues to make a clearer decision for the secretary. More importantly, a DSD focused on the services would provide a stronger service perspective in many senior decision forums. A third DSD could have authority over major issues affecting the defense enterprise, such as finances, auditing, and the information technology backbone.1 Ideally, this DSD could focus on upgrading and streamlining the DOD’s information technology to improve productivity across the department. The OSD already has offices and staff that cover these issues, but few decisionmakers. Although assistant secretaries of defense (ASD) and under secretaries of defense (USD) are 4-star equivalents who have influence, they reside outside the chain of command.
Rather than the current system, where the services control the vast majority of funding, each DSD should control a portion of the overall budget established by the secretary. This would enhance the secretary’s influence over the budget and help encourage trade-offs between services for similar mission functions. Additionally, this construct would provide a stronger pathway for CCMDs to advocate for funding of near-term priorities. This should include providing CCMDs with a method to “bid” to use extant forces while providing a clear market signal for what CCMDs truly value. These adjustments also enhance the secretary’s power by pushing less important decisions to empowered DSDs, which would allow the secretary more time to focus on major strategic issues, such as determining how to apportion funding between current and future priorities and any other issues the secretary prioritizes. When the secretary takes on a major issue, like Mine Resistant Ambush Protected (MRAP) vehicles, the DSDs can keep everything else moving. Overall, adding two DSDs and empowering them should substantially improve the benefits of CCMD consolidation without adding large additional staffs.
The United States is entering a new era of great power competition that demands more than marginal reform—it requires a new map. The current UCP reflects the world as it was, not as it is becoming. Designed for the post–Cold War moment and stretched to address everything from terrorism to near-peer rivalry, the combatant command structure has become a bureaucratic labyrinth. Each node—each four-star billet—fights for attention, resources, and relevance. Instead of generating clarity, the system multiplies friction. If Washington wants to win in the era of systems warfare and strategic competition, it must reimagine the machinery of defense—starting with the architecture of command. The recommendations that follow aim to generate more flexible options for national leadership, rebalance the relationship between current operations and future force design, and create an institutional structure that can think, compete, and adapt at the speed of relevance.
First, the DOD should significantly reduce the number of four-star CCMDs and broaden the responsibilities of each four-star commander. The CCMDs give greater emphasis to their specific problems; however, the proliferation of “priority” problems has created an arms race for bureaucratic power instead of improved prioritization and subject matter expertise on each issue. Consolidating the CCMDs into three regional commands and three functional commands provides the best first step. These consolidated CCMDs should have additional budgeting authority to purchase munitions or commercially available solutions that do not create a long-term sustainment bills.
Second, the secretary or Congress should create a deputy secretary of defense (DSD) who is in the chain of command for all of the Combatant Commands (largely current operations focused) and another who is in the chain of command for all of the services (largely future focused). Each of these DSDs would have budgetary responsibilities for the entities they are responsible for. The primary purpose of these DSDs would be resolving disputes between CCMDs or Services in accordance with secretary and presidential guidance. Today, there are too many four-star commanders with appropriately different priorities that the secretary must adjudicate. The system generally works well for important and urgent problems, but all other decisions move at a glacial pace.
Third, the options outlined in this paper require immediate attention by an interagency planning team to assess their viability. This team could—within 60 days—offer concise recommendations for the next UCP. If the DOD has more time, then a more sustained, deliberate effort should be undertaken by a mix of think tanks and federally funded research and development centers to ensure that the secretary has access to a broad range of perspectives, as well as insights from war games, that can inform the FY 2027 NDAA.
Fourth, the interagency team should also confront one of the most overlooked barriers to strategic coherence: the fact that the Department of State and the Department of Defense use different maps to see the world. This is not just a bureaucratic artifact—it is a strategic liability. When diplomats and war fighters operate on mismatched regional boundaries, they create seams that adversaries can exploit and that allies find confusing. The result is a series of missed opportunities and diminishing marginal returns in everything from security assistance to crisis response. If the United States wants to operate as a truly integrated state actor in a contested world, it needs to align its cartography. Harmonizing these maps would enhance interagency planning, create shared mental models, and help forge more coherent campaigns that blend defense and diplomacy across regions.
Reforming the Unified Command Plan is a way to support the Trump administration’s desire for a smaller, more focused federal government and national security enterprise. However, such an effort should rest on interagency coordination and rigorous analysis, including ideas outlined in this report and past work completed in accordance with the National Defense Authorization Act for FY 2022. This report provides a starting point for discussion and analysis, not a final answer.
The designers of the current UCP faced a different international situation, a different range of threats, different communication tools, and a different speed of events. Today, the U.S. administration anticipates a need to shift U.S. grand strategy to be more agile and efficient while also better aligning with changing international conditions. Administration officials have clearly signaled a desire to lower international commitments today to preserve and expand economic strength for a potential great power conflict with the PRC tomorrow. This “reordering” of national strategy will create the largest change in the international system since 1945. Fewer resources will also require the DOD to do less with less on a daily basis. Therefore, the DOD must operate differently so it can rapidly adjust training and operations as the international situation and presidential priorities change. Operating differently requires an updated military command structure to effectively use the resources the American people have given the DOD. As U.S. national strategy evolves, the military instrument must adapt to support that strategy if it is going to meet the moment. Form should always follow function.
Todd Simmons is a senior non-resident fellow in the Defense and Security Department at the Center for Strategic and International Studies (CSIS) and a professor of practice at the Marine Corps University, School of Advanced Warfighting. Colonel Benjamin Fernandes is an Army strategist at the National Defense University. Benjamin Jensen is the Frank E. Petersen Chair at the School of Advanced Warfighting and the director of the Futures Lab at CSIS.The conclusions and opinions expressed are the authors’ own and do not reflect the opinions or official position of the U.S. government, Department of Defense, National Defense University, or School of Advanced Warfighting.
This report is made possible by general support to CSIS. No direct sponsorship contributed to this report.
Please consult the PDF for references.
Please see below for an appendix summarizing options for reorganizing U.S. military command structures.
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