What the New National Security Strategy Means for Naval Forces

Commentary by Benjamin Jensen, Mackenzie Eaglen, and Henry H. Carroll

Published December 18, 2025

The 2025 National Security Strategy (NSS) has undercurrents of a classical maritime document that connects strategy to economic power. Echoes of the turn of the nineteenth century permeate the strategy, with implicit allusions to the Roosevelt Corollary, the Great White Fleet, and, most of all, Alfred Thayer Mahan's assertion of the centrality of "sea power" to the United States' national interests. The strategy narrows U.S. ambitions to focus on the Western Hemisphere while reframing great power competition as an economic and industrial contest. For the Navy and Marine Corps, that combination points toward a more hemispheric and distributed form of sea power that still has to deter China and manage nuclear-armed rivals while placing renewed emphasis on securing critical sea lines of communication. It is a mandate for more maritime constabulary work from the Caribbean to the Eastern Pacific, along with renewed attention to choke points like the Red Sea and Panama Canal. And it points toward the critical need to fix shipbuilding and field new, unmanned formations that reduce the costs of securing national interests.

Sitting behind words is an economic theory of victory. The United States must invest resources to fix its industrial base and ensure it retains the lead in AI and the energy sector. The defense budget will continue to be consumed by modernizing the nuclear triad, projected to cost $460 billion over 10 years, and building Golden Dome, with cost estimates ranging from $175 billion to $542 billion. That means conventional deterrence must identify cost-effective solutions ranging from precision mass and fielding large numbers of small drones from the seabed to space and fixing lingering maintenance issues that reduce the return on naval investments. Every $2.7 billion dollar destroyer and $4.8 billion dollar amphibious ship (by Congressional Budget Office-estimated replacement cost) down for maintenance is unproductive capital, unable to generate the effects the Navy needs to defend the homeland and deter China. As a result, fixing maintenance and shipyard productivity work alongside fielding a hybrid fleet where drones outnumber capital ships to change the economics of naval campaigns.

From Strategy to Fleet Requirements

First, the strategy claims to be the first to correctly align ends and means and move away from what it views as elite interests in globalism and free trade. Yet, as a maritime nation that relies on the oceans for its trade, the United States must preserve access to critical sea lines of communication. The maritime economy contributes $2.9 trillion to U.S. GDP and accounts for 40 percent of U.S. trade. Therefore, even an America that seeks to focus on the Western Hemisphere and issues like migration and countering illicit activity must retain its ability to project naval power. The strategy's focus on rebuilding the economic base of national power and "re-shoring" production will require secure maritime trade lanes. As Mahan wrote in 1900, "The power, therefore, to insure these [sea-borne] communications to one's self, and to interrupt them for an adversary, affects the very root of a nation's vigor."

While the NSS presents itself as a sharp break from the past, the Navy's roles and missions are not set to change much in practice. The Navy will still be called upon to project power across the globe, secure sea lines of communication for U.S. and its allied maritime trade, and defend the homeland. The greater emphasis on the Western Hemisphere and new understanding of homeland defense may change priorities within these missions, but not the overall set of missions.

Renewed Hemispheric Focus

Second, the document is replete with calls for a denial strategy that will require naval forces. There is a new "Trump Corollary" that reasserts U.S. preeminence in the Western Hemisphere and seeks to deny non-hemispheric powers control of key assets and locations. That strategic end will require a mix of unmanned surveillance vessels and creative approaches to maritime domain awareness alongside the ability to retain amphibious forces and striking power. The nation will need a stronger Coast Guard that is interoperable with the Navy and can work alongside drone ships to counter human and drug trafficking. Developing the capacity to exercise global maritime constabulary power will be required.

The Western Hemisphere is no longer an afterthought. A region relegated under several administrations to commanding just 1 percent of global intelligence, surveillance, and reconnaissance (ISR) assets, for example, is experiencing a stark turnaround. The strategy calls for rebalancing global force posture toward hemispheric missions. This shift, alongside pending changes in the Unified Command Plan hinted at with the U.S. Army's creation of a Western Hemispheric Command, imply expanding Coast Guard and Navy presence to control sea lanes, stop illegal migration, and interdict drug and human trafficking.

Practically, that points toward more patrols and forward staging in the Caribbean and elsewhere. It also could lead to expanded security cooperation and possibly new access agreements with Mexico, Central and South American states, and Caribbean partners to counter both regional authoritarian regimes and deter Russia and China from gaining a deeper foothold within the hemisphere.

For the Navy, this posture favors shifting littoral combat ships, smaller surface combatants, patrol craft, and unmanned vessels that can cover large areas and work hand in glove with law enforcement while supporting larger pressure campaigns and coercive diplomacy. This could mean optimizing the Fourth Fleet as a home for littoral combat ships and unmanned surveillance drones, creating interdiction motherships similar to concepts used in Singapore. Unmanned systems will best be able to create naval presence when paired with legacy capital ships, as while unmanned surface vehicles (USVs) can create effects, their ability to create persistence and exercise influence is relatively limited.

The underlying logic includes cost-effectiveness. The Navy will need low-cost methods for meeting the demands of Caribbean missions that don't reduce its readiness for deterring China. The United States can achieve economies of force by deploying older Navy capital ships that may prove too vulnerable for a high-end Pacific fight alongside Coast Guard cutters and affordable USVs. This approach would echo the U.S. Navy's Special Service Squadron that was formed to patrol and show the flag in the Caribbean in the tumultuous 1920s, which was primarily formed by ageing cruisers and small combatant vessels. For the Marine Corps, it suggests a need to balance the force and ensure it retains its ability for crisis response and security cooperation in the littorals without degrading its new roles and missions linked to sea denial in the First Island Chain. This likely suggests an expanded role for the Marine Corps Reserves to reduce the demand for active forces, which will be increasingly tailored to littoral defense and crisis response.

The risk is familiar. Every time the sea services become the go-to tool for near-term security problems close to home, long-range training and preparation for high-end conflict tend to erode. Hemispheric maritime operations will be important, but they can easily absorb attention and wear out ships that are also needed for deterrence in the western Pacific. This is why the fleet will need to expand its use of unmanned systems to generate cost-effective options and a larger return on investment. The United States may also find that using naval forces for coercive ends may not achieve the strategy's desired long-term objective of stability of the Western Hemisphere, given the history of tensions in the region between U.S. coercive naval diplomacy and cooperative efforts.

Continued Deterrence in the Indo-Pacific

In the Indo-Pacific, the strategy calls for maintaining a favorable military balance sufficient to deter China in the First Island Chain. This requires not just increased defense spending by key allies like South Korea and Japan, but also the ability for the United States to fight alongside them and retain forward-based naval forces. The Navy will need to invest in logistics and infrastructure that support its ability to generate combat power forward, to include exploring how to build weapons with partners. Seen in this light, frameworks like AUKUS can be the beginning, not the end, of a new era of efforts to create an allied arsenal of democracy. This creates a need for the Department of the Navy to coordinate with the Departments of War and State to change defense policy to support building capabilities with partners, including accelerating proven models like the coproduction of munitions.

The United States must possess a military that can deny aggression in the First Island Chain and keep the South China Sea open to global commerce. According to the strategy, this requires investing in "undersea, space, and nuclear, as well as other [technologies] that will decide the future of military power, such as AI, quantum computing, and autonomous systems, plus the energy necessary to fuel these domains."

This approach implies a navy built for sea denial and countering enemy kill chains. Mixes of submarines, unmanned systems, naval aviation, and littoral rotational forces will change China's cost calculus. The Navy will posture for Distributed Maritime Operations by fielding larger numbers of unmanned systems, ranging from decoys and intelligence ships to strike platforms, that can cost-effectively hold large Chinese capital ships at risk. Much of this fight will include renewed emphasis on "C5ISR-T," or blinding and confusing Chinese sensor networks and command and control to overcome their advantage in mass. That likely translates into a fleet of decoys as much as it does unmanned surveillance and strike platforms on the surface and subsurface. This produces a vision of future maritime campaigns that use a mix of drones, subs, and stand in forces-littoral regiments sitting on key islands with anti-ship missiles, integrated air defense, and persistent sensing-to fix, deter, or delay enemy formations while a larger fleet moves into position to launch pulse-type attacks from multiple domains and directions.

While the new strategy emphasizes partner burden sharing and shifting, this vision of future war relies on allies and building interoperable naval forces. Deterring China requires a network of forward staging areas and agreements to rearm and repair Navy ships forward alongside agreements that support coproduction, research, and allied supply chains. At the tactical level, it requires the ability to pass targeting information between allies and even start building key munitions and weapons systems, if not entire classes of ships, with them. That pushes the Navy toward a "framework" role where U.S. forces provide high-end enablers, command and control, and some strike capacity. Regional allies provide mass, persistent presence, and local knowledge and workers, facilities, and access to energy. Interoperability in sensors, combat systems, and munitions and effects becomes more important than sheer U.S. hull numbers. At the strategic level it creates stand-in contested logistics force able to generate combat power inside China's anti-access/area denial (A2/AD) bubble.

Furthermore, since the strategy treats economic competition as the primary contest with China, naval power will be used to underpin sanctions, export controls, and control of strategic sea lanes. Maritime interdiction operations, protection of logistics, and resilience of allied shipping networks sit at the heart of deterrence. They also support a vision of blockading China as a means of seeking an offramp during a deadly conflict, though the naval force required to implement such a blockade would be immense.

The challenge is in part temporal. Reindustrialization, shipbuilding at scale, and allied capacity building could take a decade, while the potential window for conflict around Taiwan is often assessed in months to a few years.

Rebalancing Europe and the Middle East

Last, the strategy stresses the need for the United States to pull back from "forever wars" in the Middle East and reduce forward-deployed forces in Europe. Read carefully-the document doesn't end U.S. alliance commitments. Rather, it seeks a rebalancing that requires more flexible force generation and deployment models that allow Washington to focus on the Western Hemisphere and deter China in the First Island Chain. This implies preserving flexible crisis response forces like Expeditionary and Carrier Strike Groups that don't require large, forward troop garrisons. And it implies finding ways to address readiness and maintenance challenges in these formations to ensure naval power projection can effectively reduce geopolitical risk in Europe and the Middle East.

In Europe, the strategy's message is blunt. The United States will help negotiate an end to the war in Ukraine, reestablish strategic stability with Russia, and support European prosperity, but Europeans must take primary responsibility for their defense and avoid being dominated by any adversarial power.

For the Navy, that likely means fewer continuous carrier strike group deployments to the Mediterranean and North Atlantic, especially as it addresses its chronic ship maintenance issues. The United States will still support its partners, but its presence will be more episodic and linked to using exercises as a form of military signaling that supports deterrence. Interoperability will have to grow given the greater reliance on allied naval forces, including the increasingly capable Nordic, Baltic, and Mediterranean fleets. The Navy will have to work with Pentagon war planners to identify the optional mix of enablers that increase allied combat power, while freeing up ships for the Western Hemisphere and Indo-Pacific. This could see greater reliance on unmanned aircraft, including collaborative combat aircraft, working alongside maritime patrol aircraft and airborne command and control assets such as the E-2D.

In the Middle East, the strategy frames energy diversification and U.S. production as reducing the region's centrality. The Navy's missions will be to keep the Strait of Hormuz and Red Sea open, prevent terror threats, and support partners, especially Israel and the Gulf states, while avoiding large ground deployments.

This objective will require a similarly episodic regional presence, likely built around surface action groups and carrier strike groups. The United States will need to signal it can strike inland targets and counter hostile attempts to control key maritime choke points. The strategy puts a premium on long-range maritime strike, minesweeping, and convoy operations that can surge during a crisis without permanently tying down ships and crew. Marine forces are better allocated to the Indo-Pacific and maintained as a global crisis response force.

How the National Security Strategy Shapes Naval Forces

The 2025 National Security Strategy provides a strategic blueprint for thinking about how the U.S. naval services will adapt to the ongoing fundamental shifts in U.S. priorities and national interests. It provides Navy leaders trade space to rebalance toward high-end deterrence in Asia, while modernizing the industrial base and tackling hemispheric threats with appropriate forces.

The Navy will need to implement its response to this strategic shift thoughtfully. It should consider accelerating, expanding, and incentivizing innovation in its unmanned vessel and aviation programs, which will play key surveillance roles in the Western Hemisphere and critical combat support and offset roles in a potential high-end conflict in the Indo-Pacific. The Navy will also need to shift some of its more vulnerable legacy manned combatants out of the Indo-Pacific and rely more heavily on USVs, subsurface capabilities, and littoral regiments alongside select advanced surface platforms. Legacy vessels can remain relevant in regions where presence and signaling strike capability are more important than distributed survivability, such as Latin America and the Middle East. Moreover, the Navy should continue working to expand capacity and improve the efficiency of the industrial base for both manned and unmanned vessels as it builds the readiness needed to deter China and defend the homeland.

The new National Security Strategy elevates sea power in quiet ways. It calls for control of sea lanes in the Western Hemisphere, denial of aggression across the First Island Chain, protection of global choke points from Hormuz to the Red Sea and Panama, and modernization of undersea, nuclear, and missile defense capabilities. The Navy and Marine Corps now must turn those broad directions into real ships, formations, and concepts that can operate at home and abroad.

Benjamin Jensen is director of the Futures Lab and a senior fellow for the Defense and Security Department at the Center for Strategic and International Studies (CSIS) in Washington, D.C. Mackenzie Eaglen is a senior fellow at the American Enterprise Institute (AEI), where she works on defense strategy, defense budgets, and military readiness. Henry Carroll is a research associate with the Center for the Industrial Base at CSIS.

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