National Defense Strategy: Potential Implications for DOD of Prioritizing the Western Hemisphere and China

National Defense Strategy: Potential Implications for DOD of Prioritizing the Western Hemisphere and China

National Defense Strategy: Potential Implications for DOD of Prioritizing the Western Hemisphere and China

December 18, 2025 (IF13137)

The 2025 U.S. National Security Strategy (NSS) outlines the second Trump Administration's aim to shift how U.S. foreign policy prioritizes different regions of the world. The shift in regional priorities outlined in the document could lead to changes in U.S. defense strategy, plans, programs, and operations. Such changes could affect, among other things, the locations and numbers of U.S. forces; the locations of military facilities; the types and quantities of weapons and equipment the military develops and acquires; and the alliances and partnerships that support U.S. basing and overflight, defense production, and integrated training. Congress may act to support, reject, or modify this prioritization through legislation (including appropriations) and oversight.

The 2025 NSS and past NSSs have named the U.S. sovereignty, safety, and prosperity as a priority, but have outlined different paths to securing it. The Biden and first Trump Administrations' strategies of 2022 and 2017, respectively, emphasized great power competition with China and Russia. The 2025 NSS, by comparison, includes a focus on defending the U.S. homeland by "reassert[ing] and enforc[ing] the Monroe Doctrine to restore American preeminence in the Western Hemisphere," and competing with China economically and militarily in the Indo-Pacific region. Defense of the U.S. homeland, the 2025 NSS states, includes countering mass migration, drug trafficking, and foreign incursion in the region, and defending against complex aerial threats with the Golden Dome for America missile defense system. Compared with the 2017 and 2022 NSSs, the 2025 NSS places less emphasis on competition with Russia, potential Russian threats to European security, or competition with China and Russia in the Middle East and Africa.

The 2025 NSS calls on the military to "[readjust] our global military presence to address urgent threats in our Hemisphere," "[deter] a conflict over Taiwan, ideally by preserving military overmatch" with China, and "[enable] Europe to ... [take] primary responsibility for its own defense." The second Trump Administration's National Defense Strategy (NDS), which has not been publicly released as of December 18, 2025, may detail how the Administration anticipates this strategy will be implemented by the Department of Defense (DOD, which is "using a secondary Department of War designation," under Executive Order 14347 dated September 5, 2025).

Potential Implications for DOD

Proposed regional reprioritization, as described in the NSS, may lead to shifts in DOD strategy, plans, programs, and operations. These potential shifts include the following:

Repositioning U.S. Forces. DOD may reduce military personnel and equipment (including prepositioned stocks) based in Europe and the Middle East, and increase personnel and equipment in the Western Hemisphere and/or the Indo-Pacific region. It may also reduce or reallocate rotational deployments. Geographic combatant commands may change their organization, posture, plans, presences, and security cooperation activities. Troop reductions in Europe or the Middle East may mean moving forces back to the United States. If so, hosting these forces domestically may require time and funding to build additional basing facilities.

Acquisitions for Homeland Defense. DOD may emphasize homeland defense programs, including the Golden Dome for America missile defense system, capabilities to monitor and defend sea and air approaches to the United States, and capabilities to assist other U.S. agencies in countering drug trafficking and illegal immigration into the United States.

Acquisitions for "Military Overmatch" of China. The services may prioritize acquiring weapons that are better suited for deterrence in the Indo-Pacific region than in deterrence in Europe, such as

long-range crewed and uncrewed aircraft and weapons that effectively operate outside the range of China's anti-access/area-denial (A2/AD) systems,

platforms (e.g., submarines) for operating effectively inside the range of China's A2/AD systems, and

long-range logistics capabilities (including airlift and sealift) to support U.S. combat forces in the Western Pacific that are further from the United States than are locations in Europe.

DOD may also deemphasize efforts to develop and procure armored fighting vehicles, tube artillery, and other land systems that are more relevant in a conflict in Europe than in the Indo-Pacific or Western Hemisphere.

Facilities and Footprints. DOD may invest in military construction to create, reopen, and improve military bases, supply points, and repair facilities in the Western Hemisphere and Indo-Pacific, including in locations in U.S. states and territories, and allied and partner countries.

Past Administrations have expressed a goal of reducing U.S. military presence and operations in a given region (e.g., the Middle East) but encountered challenges due to international commitments and unanticipated crises. The second Trump Administration may be similarly constrained in implementing the 2025 NSS. For example, U.S. treaty commitments to NATO may constrain U.S. options for reducing presence in Europe, if that is the Administration's desired end state.

However, some of the potential changes discussed above have already begun, both under the second Trump Administration and previous Administrations. For example:

The Navy began shifting a greater share of its ships from the Atlantic Fleet to the Pacific Fleet starting in 2006.

The Air Force has gradually positioned more advanced, combat-coded fighter aircraft units in the Pacific, and plans to continue to do so. It has armed some of its aircraft with air-launched anti-ship missiles. It has also rotated bomber aircraft into Guam and other locations since 2004.

The Army and Marine Corps, in 2019, initiated efforts to field land-based anti-ship missiles, and the Army began developing a land-based hypersonic missile.

DOD began increasing infrastructure investments in the Indo-Pacific under the first Obama Administration and is reportedly reopening and upgrading bases in the Caribbean Sea in 2025.

Issues for Congress

Congress may act to support, reject, or modify priorities outlined in the 2025 NSS. It may do so through legislation (including appropriations) and oversight.

Issues for Congress include the following:

How might troop increases and decreases in various theaters affect regional deterrence and stability, alliances and partnerships, and U.S. ability to respond to regional contingencies? Congress may consider whether or not to limit the executive branch's authority to increase or reduce troop numbers in a region without notification of or consultation with Congress.

How might increased or decreased investment in certain capabilities affect the U.S. defense industrial base (DIB) in the short and long term? Congress may direct studies into how implementing the NSS might affect the DIB.

Does Congress, through the NSS, NDS, or other means, have sufficient insight into the Administration's global political aims and its defense strategy to achieve those aims? Congress may consider whether or not to amend or remove statutory requirements for these documents, or to require additional reporting or testimony.

To what degree does the FY2026 President's budget request reflect the 2025 NSS, and to what extent will the NDS and FY2027 request, including the Future Years Defense Program (FYDP), do so? Congress may consider whether and how much to fund certain capabilities and activities aimed at implementing the NSS (or other congressional priorities).

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