MAGA Geopolitics in the Second Trump Administration and the Republic of Korea's Strategy of Compartmentalization 

Chansong C. Lee

clee@sejong.org

Research Fellow

Sejong Institute

1. MAGA Geopolitics in the Second Trump Administration

What are the defining foreign policy principles of Donald J. Trump’s second presidential administration? President Trump’s 2025 inaugural address, echoing themes from eight years earlier, emphasized protectionism, anti-immigration policies, non-interventionism, and American exceptionalism. However, it also incorporated newly emergent expansionist elements. Amid these conflicting orientations, senior officials appointed by President Trump tried to sanewash his erratic behavior and inconsistent approach to foreign policy.

However, rather than focusing on Trump’s exaggerated rhetoric and actions—often calculated for transactional purposes—it is necessary to adopt a more impersonal approach in order to evaluate the foreign policy of his second administration. Given the deluge of policies introduced within within a short period, one can infer the presence of an underlying driving force that loosely integrates these otherwise fragmented initiatives. In particular, understanding the affect—the latent experiences of emotions, feelings, and moods—among Trump’s supporters is crucial. Within this discourse, one finds hostility toward elites and outsiders, accompanied by sentiments of loss, despair, betrayal, anger, and fear. At a deeper psychological level, this affect is encapsulated in a shared perception: “we were deceived, we were robbed, and we have no future.”

To comprehend the MAGA geopolitics of Trump’s second administration, it is essential to situate it within the longer historical trajectory of U.S. foreign policy, particularly the Monroe Doctrine and the ideology of “Manifest Destiny,” both of which underpinned nineteenth-century American territorial expansion. Furthermore, MAGA populism itself must be understood as a domestic political phenomenon shaping the administration’s external behavior.

The Monroe Doctrine originated with President James Monroe’s address to Congress on December 2, 1823. It was formulated against the backdrop of perceived threats from European powers to the security of the United States and its surrounding territories, as well as to U.S. commercial interests in the Western Hemisphere. To counter these threats and preserve its economic influence, the United States declared its opposition to any European intervention in the Americas. By contrast, “Manifest Destiny” was not an official doctrine but a widely embraced belief that white Americans possessed a divine obligation and inherent right to dominate the North American continent. The ideology served as a foundation for American exceptionalism, white nationalism, and westward expansionism throughout the nineteenth century.

The MAGA geopolitics of Trump’s second administration operates as a complex amalgamation of these historical impulses, grounded in a populist-nationalist political base. It combines a Jacksonian-style aggressive expansionism reminiscent of mid-nineteenth-century U.S. foreign policy with a modified version of the Monroe Doctrine as articulated during the late nineteenth century, particularly under Presidents McKinley and Theodore Roosevelt.

MAGA geopolitics, as a distinct dimension of the foreign policy of Trump’s second administration, seeks to maximize U.S. national interests and restore what is perceived as America’s declining relative power. It does so by leveraging geopolitical instruments such as territorial expansion, territorial control, and transactional approaches to territorial relations. In practical terms, this orientation translates into three broad strategic tendencies: first, the delineation of regional boundaries to preventively address offshore geostrategic and geoeconomic threats; second, the reinforcement of U.S. control and influence within proximate regions through coercive measures; and third, the strategic abandonment of distant regions deemed of marginal importance to U.S. interests. The cumulative effect of these strategies is a deliberate retreat from the traditional American role in constructing and sustaining a liberal international, coupled with a reduction of asymmetric interdependence with external regions.

Therefore, MAGA geopolitics can be understood as embodying three distinct strategic orientations: indifference toward issues not directly relevant to U.S. interests, coercion in defense of core U.S. interests, and, a transactional approach toward matters that may potentially align with U.S. interests. In other words, it entails a tripartite division of global regions into zones of abandonment, transaction, and coercion. The special boundaries of MAGA geopolitics under a second Trump administration correspond to the imagined frontier of the United States as envisioned by proponents of Manifest Destiny. These boundaries are delineated in light of the historical expansion of U.S. power, status, and technological capabilities over the two centuries.

Withing this region lie United States’ core interests, where Washington is expected to engage in coercive diplomacy. Beyond this zone, other regions are differentiated primarily by their geographic distance from the United States as well as their strategic and resource value. However, the boundary between areas of transaction and abandonment remains fluid, depending on the specific configuration of so-called “peripheral interests.” Most U.S. allies occupy the transactional zone, while states such as Türkiye, Thailand, and Pakistan are positioned closer to the sphere of abandonment. Africa is generally viewed as a zone of abandonment, yet resource-rich states-such as the Democratic Republic of the Congo, with its significant cobalt reserves—may be shifted into the transactional category. Similarly, Ukraine is expected to be situated along the boundary between transactional and abandonment zones.

2. Strategic Instruments of MAGA Geopolitics

A. Regional Demarcation of Core Interests and the Enhancement of Regional Defense Capabilities

The defining feature of MAGA geopolitics is the delineation of an expanded sphere of core interests, accompanied by the pursuit of preemptive and preventive measures against geostrategic and geoeconomic threats originating from external regions. Achieving this objective necessitates the extension of territorial influence and the consolidation of territorial control.

For Trump, a former real estate entrepreneur, the concepts of "lines" and "areas"—such as borders, boundaries, and divisions—carry particular significance. He frequently employed territorial metaphors derived from the real estate sector, framing geopolitical considerations in spatial and property-related terms. His approach often reflected a geoeconomic logic, assessing territorial value based on prospective returns, resource endowments, and potential for future development.

Within this framework, the MAGA geopolitics of a second Trump administration could entail both the expansion of areas under direct U.S. control and the establishment of buffer zones along newly delineated boundary lines. By designating the space within these boundaries as America’s backyard, this strategy asserts regional privileges while seeking to offset external geostrategic and geoeconomic threats through preemptive and preventive measures.

Specifically, Greenland holds significant geostrategic value for the defense of U.S. mainland. The perceived inadequacy of NATO's defensive capabilities in responding to emerging strategic threats in the Arctic provides a potential justification for stronger U.S. territorial control over Greenland. In addition, the island’s vast natural resources and the prospective opening of the Northeast and Northwest maritime passages have heightened U.S. geoeconomic interest in the region.

Similarly, Panama occupies a role for the United States comparable to that of Crimea for Russia. The United States facilitated Panama’s separation from Columbia to secure construction of the Panama Canal and later transferred control of the canal to Panama in 1999, framing it as an act of goodwill. However, Washington now perceives growing geoeconomic threats from China’s presence and influence in the Panama region.

Furthermore, Canada represents a strategic and resource-based opportunity: as the second-largest country in the world with abundant natural resources, its hypothetical annexation could make the United States the world’s largest state by both territory and resource endowment. Finally, the Indo-Pacific dimension of U.S. territorial strategy remains constrained in terms of direct territorial expansion. Nonetheless, Washington retains avenues for indirect influence through the Compact of Free Association and is likely to pursue stronger control over existing U.S. Pacific island territories to reinforce its geostrategic posture in the region.

In conjunction with efforts at territorial expansion and consolidation of control, the United States is expected to enhance its territorial defense posture. The issuance of the executive order “The Iron Dome for America” marks a significant shift in U.S. missile defense strategy. This policy not only represents a reorientation toward strengthened homeland protection but also establishes a virtuous cycle with the expansion of U.S. space-based defense capabilities, reinforcing layered deterrence and strategic resilience.

B. Policy Enforcement and Regional Governance through Interventionist Practices

Within the framework of MAGA geopolitics, the United States is expected to employ coercive diplomacy toward states situated within regions designated as vital to its core interests. Such an approach would involve exerting economic, political, and diplomatic pressure to compel these states to revise domestic policies—particularly in areas such as trade, investment, and immigration—in ways that align more closely with U.S. national priorities.

In particular, the United States frames the fentanyl crisis as both a geostrategic and geoeconomic challenge, attributing its origins primarily to China while regarding Canada and Mexico as passive bystanders. To address this issue, Washington has considered designating Mexican drug cartels as Foreign Terrorist Organizations (FTOs) and expanding cross-border drone surveillance to disrupt trafficking networks.

The U.S. Trade Facilitation and Trade Enforcement Act of 2016 established a de minimis threshold that exempts imported goods valued under $800 from import duties and customs inspections. Approximately 60 percent of imports benefiting from this provision originate from China, leading policymakers to view it not only as a contributing factor to the U.S. trade deficit with China but also a potential conduit for fentanyl precursor chemicals. Consequently, the Trump administration moved to abolish the duty exemption system for low-value imports and imposed additional tariffs on China, Canada, and Mexico, framing these measures as necessary for combating the fentanyl crisis rather than initiating a broader trade war. As Secretary of the Interior Doug Burgum stated, these policies were intended as a proactive response to what he described as a “massive fentanyl invasion” that contributes to an average of over 300 overdose deaths per day in the United States.

The second Trump administration has indicated its intention to designate eight major Latin American cartels as FTOs and to implement counterterrorism measures under the provisions of the Immigration and Nationality Act. Such a designation would expand the legal basis for employing U.S. military power within Mexican territory and enhance the scope for inter-agency coordination in counter-cartel operations. Concurrently, the administration frames immigration as a form of territorial incursion or invasion, thereby justifying heightened pressure on Canada and Mexico to strengthen border security measures. This approach is likely to be accompanied by the implementation of an expansive deportation policy targeting undocumented migrants, aligning domestic enforcement with broader geostrategic objectives.

C. A Selective Approach to Peripheral Regions: Differentiating Between Zones of Neglect and Transaction

Within the framework of MAGA geopolitics, the Trump administration is expected to deprioritize extra-regional areas where U.s. national interests are minimal or negligible, effectively designating them as zones of neglect. Conversely, regions possessing strategic assets or valuable resources may be classified as transactional zones, where engagement is pursued primarily through quid pro quo arrangements. The distinction between neglect and transaction is not fixed but exists along a fluid spectrum, subject to recalibration based on shifting geopolitical conditions and U.S. bargaining power.

What distinguishes MAGA geopolitics from traditional geopolitical theories, such as those of Mackinder or Spykman, is its departure from a strategy of long-term containment of Eurasia (Russia) or the Rimland (China). Instead, it partially acknowledges the spheres of influence of these great powers, seeks to stabilize their peripheries through transactional arrangements, and demonstrates a marked preference for consolidating territorial control within the Western Hemisphere. In this context, the United States imposes trade restrictions on its European and Indo-Pacific allies, while showing limited willingness to intervene militarily to secure Middle Eastern resources. This approach reflects a broader retreat from traditional internationalism and envisions the construction of a self-sufficient economic bloc anchored in the Western Hemisphere, thereby reducing reliance on extra-regional markets and supply chains.

On January 20, 2025, the Trump administration issued an executive order temporarily suspending all foreign aid for a 90-day review period, after which it announced a decision to reduce aid allocations by 80 percent. This policy shift is expected to have its most immediate and pronounced impact on Ukraine, Pakistan, and several African states. Nevertheless, Washington has demonstrated sustained interests in the Democratic Republic of the Congo due to its substantial cobalt reserves, as well as in other regions rich in rare earth elements and strategic minerals. For similar reasons, a complete disengagement from Ukraine appears unlikely, as its geopolitical position and resource potential continue to hold transactional value for U.S. strategic calculations.

The Trump Administration, seeking to reduce its defense budget by approximately 8 percent annually over the next five years, outlined its priority areas for defense spending. Funding for operations along the U.S. southern border, nuclear weapons modernization, missile defense programs, submarine procurement, acquisition of loitering munition drones, and efforts to dismantle transational criminal organizations in the Western Hemisphere was explicitly exempted from budget cuts. Budgetary allocations were concentrated on the Indo-Pacific Command (INDOPACOM)--tasked primarily with countering China—and the Northern Command (NORTHCOM), responsible for homeland defense. In contrast, the European Command (EUCOM), Central Command (CENTCOM), and Africa Command (AFRICOMN) did not receive increased support under this revised framework. The fiscal savings generated from these cuts were earmarked for strategic initiatives such as the Iron Dome for America project, aimed at strengthening missile defense capabilities for the U.S. mainland.

3. The Republic of Korea’s Strategy of Compartmentalization

Within the cartographic framework envisioned by the Trump administration’s MAGA geopolitics, South Korea occupies a transactional zone, rather than a zone of abandonment as it once did when positioned outside the historical Acheson Line. Owing to its advanced manufacturing capabilities—in sectors such as shipbuilding, automobiles, and semiconductors—and its geographic proximity to China, the Republic of Korea (ROK) retains substantial strategic utility for U.S. interests in the Indo-Pacific. Recent public statements by senior officials within the Trump administration have underscored this perception, repeatedly emphasizing the indispensable role of South Korea as a transactional partner in Washington’s evolving geoeconomic and geostategic calculus.

However, the Republic of Korea is distinct from states located within the zone of coercion, such as Canada, Mexico, and Panama. Should a U.S. competitor gain influence over South Korea, the direct and immediate impact on U.S. national security would be less pronounced than in these other cases. Nonetheless, Seoul retains significant strategic value as a contributor to regional stability, a counterweight to China, and a participant in U.S.-centered economic networks, making outright abandonment unlikely. In this context, South Korea is treated as a transactional partner, subject to varying degrees of bargaining and negotiation in pursuit of U.S. interests. The longstanding prospect of “Korea Passing”—where South Korea’s interests are sidelined in high-level U.S.-China or U.S.-North Korea diplomacy—is likely to persist under this approach. At the same time, Seoul is expected to engage independently with Washington on contentious bilateral issues, including increased defense cost-sharing arrangements and the adjustment of the mission and posture of U.S. Forces in Korea (USFK).

This paper proposes a strategy of compartmentalization for the Republic of Korea in response to the MAGA geopolitics of the second Trump administration. As a security strategy, compartmentalization sets the ROK’s national security objectives as follows: (1) safeguarding the nation against threats posed by the Democratic People’s Republic of Korea (DPRK), (2) promoting stability on the Korean Peninsula and in its immediate surrounding regions, and (3) enhancing national power as a foundation for eventual unification. The strategy entails delineating distinct regional spheres—the Korean Peninsula, Northeast Asia, East Asia, and the broader Indo-Pacific—and explicitly differentiating between South Korean and U.S. interests within these domains. It further involves analyzing the points of entanglement and separation between regional issues to avoid unnecessary strategic coupling. Under this framework, Seoul seeks to establish a defense perimeter through transactional engagement with Washington while simultaneously minimizing extraneous entanglements with non-core regions and strengthening its own independent deterrence capabilities.

South Korea should gradually expand its defense perimeter to encompass Northeast Asian region, while permitting limited U.S. strategic flexibility and simultaneously minimizing its entanglement in extra-regional dynamics. To mitigate the heightened geopolitical risks that may arise from U.S. operational flexibility, Seoul could seek to offset American pressure for increased defense cost-sharing by negotiating reciprocal U.S. commitments to bolster South Korea’s own defense capabilities. Given that the post-Trump strategic environment may prove even more unpredictable than the second Trump administration itself, South Korea must exercise prudence in sustaining its alliance with Washington. This will require a dual approach: enhancing medium- to long-term deterrence capabilities and managing relations with neighboring states in a stabilizing and non-escalatory manner, thereby safeguarding national security while preserving strategic autonomy.

In the domain of national defense, Seoul should gradually expand its defense perimeter to encompass the broader Northeast Asian region. While South Korea’s core security interests remain centered on the Korean Peninsula, U.S. strategic priorities are increasingly defined by the containment of China. As Washington applies greater pressure on Seoul to align with this objective, a measured and phased extension of South Korea’s defense posture into Northeast Asia will be necessary. Within this framework, limited U.S. strategic flexibility—referring to the flexible deployment and stationing of U.S. forces on the Korean Peninsula to support deterrence and defense operations across the Indo-Pacific—will likely be unavoidable. However, this flexibility should primarily apply to U.S. Air Force assets stationed in Korea, and close bilateral consultations must precede any force employment decisions. Increased strategic flexibility, if carefully managed, could create an opportunity for Seoul to secure enhanced and more frequent deployments of U.S. strategic assets to the Korean Peninsula, thereby strengthening deterrence. To serve effectively as a security hub for permanently or rotationally deployed U.S. forces, South Korea must enhance its indigenous defense capabilities while simultaneously countering disproportionate U.S. demands for increased defense cost-sharing through calibrated negotiation and reciprocal burden-sharing arrangements.

Another critical defense priority for South Korea is the strengthening of its missile defense capabilities in close coordination with the United States. An executive order issued by President Trump instructed U.S. defense authorities to explore measures for enhancing missile defense systems for forward-deployed U.S. forces and allied nations. Similarly, the Iron Dome for America Act, introduced in February 2025, recommended the exchange and integration of missile defense technologies with trusted allies. Seoul can leverage the heightened geopolitical risks associated with the expansion of U.S. strategic flexibility to advocate for greater cooperation and technology transfer in this domain. By linking enhanced missile defense collaboration to the broader alliance framework, South Korea can secure access to advanced U.S. missile defense technologies essential for its national security, while simultaneously reinforcing bilateral deterrence capabilities in the region.

It is also essential for South Korea to strengthen its long-term strategic capabilities through enhanced maritime security cooperation with the United States. In particular, the existing framework for Maintenance, Repair and Overhaul (MRO) collaboration should be broadened in scope and fully operationalized, enabling more robust support for U.S. naval assets in the region. The Ice Pact agreements, signed during the Biden administration with Finland, Canada, and other partners to jointly construct icebreakers, trace their origins to policy initiatives from the first Trump administration. At present, the United States operates only two Arctic-capable icebreakers, in stark contrast to Russia’s projected fleet of approximately 60 icebreakers, while China is actively pursuing the development of nuclear-powered icebreakers. Given its advanced shipbuilding capabilities, the Republic of Korea is well-positioned to contribute to U.S. Arctic security efforts by constructing icebreakers that would bolster Washington’s ability to navigate and secure Arctic sea lanes. This cooperation would not only enhance U.S. capabilities in the region but also elevate South Korea’s strategic value as a maritime security partner.

Seoul must strengthen its diplomatic engagement with Beijing to provide reassurances amid adjustments to its defense posture. South Korea should consistently affirm the principle that its defense policy is not aimed at any particular country, framing the enhancement of its defense capabilities as a minimum and necessary response to an evolving strategic environment. It is crucial to emphasize that these measures are flexbile and defenseive in nature, rather than offensive or escalatory. The Republic of Korea remains commited to the One China principle and upholds a pacifist stance, opposing any unilateral attempts to alter the regional status quo by force, including on the Korean Peninsula. At the same time, Seoul must underscore that the ROK-U.S. alliance constitutes the foundation of its national security, while clarifying that South Korea has no intention of participating in offensive or destabilizing policies that could threaten neighboring states.