A regionally-centered homeland missile defense posture remains an important component of U.S. homeland defense, where evolving threats create opportunities to expand complementary capabilities across a broader continental architecture. These threats mean that what was once a relatively narrow problem of limited, predictable long-range ballistic attacks has now broadened into one that includes maneuvering hypersonic glide vehicles, low-flying land-attack cruise missiles, directional ballistic reentry systems, and other delivery concepts that compress warning time and erode fixed northern engagement geometry. As the threat environment evolves, additional investment opportunities outside Alaska can complement existing homeland-defense capabilities to fully engage, and grow, America’s defense industrial base and economy (Director, Operational Test and Evaluation [DOT&E], 2025).

In 2022, a Department of Defense Missile Defense Review stated that emerging ballistic, cruise, and hypersonic threats pose an “expanding and accelerating risk” to the homeland and that new long-range missile and space systems increasingly blur the line between regional and homeland defense. DOT&E’s FY2024 operational assessment likewise emphasized that the Ground-based Midcourse Defense (GMD) system has demonstrated homeland defense only against a small number of long-range ballistic threats using simple countermeasures and only when supported by the full sensor architecture of the broader Missile Defense System (Department of Defense [DoW], 2022; DOT&E, 2025).

Alaska remains valuable for Arctic warning, but should no longer be treated as the center of gravity for homeland defense investment. For example, the Long-Range Discrimination Radar (LRDR) at Clear Space Force Station, and the legacy Ground-based Midcourse Defense and Next Generation Interceptor (GMD/NGI) mission set are aimed at limited rogue-state ballistic threats. The 2024 DoW Arctic Strategy highlights the risks associated with insufficient Arctic early-warning and air-defense sensors while also emphasizing a broader “monitor-and-respond” enterprise involving sensing, communications, allied integration, and space-based missile-warning capabilities rather than an Alaska-exclusive solution (DoW, 2024). In other words, Arctic defense is a 50-state problem, not a single state solution. 

A continental architecture includes, but is not focused on, Alaska as an Arctic warning and interceptor node, and instead prioritizes additional investments across the lower-latitude northern tier and inland West. States such as Montana, Wyoming, North Dakota, Idaho, and adjacent inland-West locations are attractive because they provide increased detection and warning time, strategic depth, multiple engagement opportunities, better logistics, protected communications and power access, and closer proximity to the population centers, transportation nodes, strategic forces, and industrial assets actually being defended. The same argument extends eastward across the Great Lakes and Northeast border states, which sit nearer the defended urban-industrial corridor while aligning with NORAD’s emerging continental surveillance network (VanHerck, 2021; Guillot, 2025 Department of National Defence Canada, n.d.; DAF, 2025a; OTHR Northwest EIS, n.d.).

A Changing Threat Geometry

The historical Alaska-first design was developed for a threat environment characterized primarily by predictable polar or North Pacific ballistic trajectories. That assumption no longer holds true. Instead, modern ballistic threats are redefining the physics of freedom of maneuver based on geographic distance and response time. The National Air and Space Intelligence Center (NASIC), as well as numerous academic research articles, provide readily available data on hypersonic glide vehicles’ dynamics, hypersonic speed, and flight paths at lower altitudes compared to typical ballistic missiles. 

NASIC also notes that depressed trajectories and boost-, midcourse-, or terminal-phase maneuvers complicate missile defense operations. Those features reduce the value of fixed intercept geometry optimized for classic midcourse ballistic flight (National Air and Space Intelligence Center [NASIC], 2017; Fontana et al., 2022). Combined with the remarkable penetration of critical academic research by adversaries, particularly in Arctic fields of study, these developments underscore the value of complementing existing homeland-defense concepts with additional distributed capabilities.

Concurrently, academic literature increasingly supports the conclusion that future homeland defense architectures cannot rely exclusively on the northern ballistic-warning geometries that shaped Cold War missile-defense planning. Fontana, d’Errico, and Di Vito (2022) note that long-range missile-defense effectiveness is increasingly constrained by sensor limitations, tracking continuity, radar-horizon effects, and the growing complexity of advanced missile threats. Research on hypersonic glide vehicles similarly demonstrates that maneuvering trajectories, lower-altitude flight profiles, and unpredictable flight paths complicate detection, tracking, and interception compared to traditional ballistic missiles (Wang et al., 2025; Wright & Tracy, 2023). 

Increasingly, U.S. Government (USG) policy documents now reflect a shift in thinking. The 2022 Missile Defense Review states that adversaries are integrating more advanced missile capabilities into their strategies, that ballistic, cruise, and hypersonic threats are all growing, and that new long-range missile and space systems have clear implications for regional and homeland defense. In a separate 2023 MDA budget briefing, officials explained that Russia and China are developing advanced missiles launchable from aircraft, ground launchers, ships, and submarines, and that hypersonic missiles present a new challenge because they travel at exceptional speeds with unpredictable flight paths. (DoW, 2022; Missile Defense Agency [MDA], 2023) Cruise missiles further complicate an Alaska-centered geometry because they are a different sensing and engagement problem altogether. 

NORAD and USNORTHCOM’s own threat descriptions point in the same direction, recognizing that adversaries threaten the United States in all domains and from all vectors. Public examples include Russia’s long-range cruise missiles and hypersonics that complicate defense against attacks from air and sea, enabling strikes from “virtually any vector” because of extreme range and endurance. China’s emergence in space-based capabilities similarly demands a layered sensing grid and a fused ecosystem of networked sensors extending from space to the seafloor. The PLA’s deployment of a fractional orbital bombardment system (FOBS) in the summer of 2021 demonstrated how the U.S. can be held at risk from any direction (Kurokawa, 2022).  In 2025, NORAD and USNORTHCOM reiterated that a widely distributed, layered domain-awareness network from the seabed to space is the top priority for detecting and tracking threats approaching North America (VanHerck, 2021; Guillot, 2025).

Alaska's Role Within a Distributed Homeland Defense Network

Arctic deterrence, maritime access, research security, and burden sharing across allies and partners are essential for homeland defense. This requires the integrated capabilities of all 50 states and the full mobilization of America’s defense industrial base, scientific enterprise, logistics architecture, and allied diplomacy. America’s coastal and inland regions collectively provide space operations, missile warning, cyber defense, intelligence integration, and advanced research infrastructure that enable early warning and rapid decision-making across the homeland-defense enterprise.   

Alaska still matters because the Arctic remains a principal avenue of approach and billions of dollars of investment in substantial existing homeland-defense infrastructure is already there, though much of it is focused on supporting efforts in the USINDOPACOM Area of Responsibility (AOR). Clear Space Force Station’s LRDR is now operationally accepted and specifically designed to provide search, tracking, and discrimination capability in support of homeland defense and GMD fire control (DoW, 2024; U.S. Space Force, 2026). Alaska also remains integral to the GMD/NGI mission, with an increase to 64 interceptors scheduled by the end of the decade. The 2022 Missile Defense Review similarly commits to improving GMD reliability and augmenting it with 20 NGIs and expanded space and ground sensors (DoW Comptroller, 2024; DoW, 2022).

More importantly, the same official material clarifies the specific mission scope of Alaska-centered GMD capabilities. GMD has demonstrated capability against an explicit set of long-range ballistic threats, employing simple countermeasures, and only when supported by the full architecture of MDS sensors. MDA’s FY2024 budget briefing was even more explicit that GMD serves as the continuously available homeland defense capability against today’s rogue-state ballistic missile threats and that the system was activated in 2004 to defend against limited attacks from countries such as North Korea and Iran. In other words, the official mission set of Alaska-based GMD is bounded; it is not an all-azimuth, all-threat shield for the modern missile environment, which is readily achievable when all 50 states bring to bear their respective capabilities (DOT&E, 2025; MDA, 2023).

If we invest more heavily in continentally distributed architecture, we will be able to keep functioning if one geographic cluster is disrupted by weather, logistics failure, cyberattack, kinetic attack, or simply unfavorable engagement geometry against a specific threat trajectory. In other words, constructing a highly redundant and interoperable, geographically distributed system should drive investment (DOT&E, 2025). A further reason to prioritize homeland-defense investment outside Alaska is its limited security support network when threatened by domestic sabotage. Alaska is the least densely populated state, with a myriad of restricted corridors and long response times from a limited law enforcement and/or state security apparatus. Small adversarial teams, proxy actors, drone operators, cyber-enabled saboteurs, insider threats, and other hostile actors are an increasing threat and will become a complex and layered problem during a time of crisis or conflict, particularly as the defense enterprise requires rapid coordination. The northern tier, inland west, Great Lakes, Northeast, and other continental defense nodes offer a more robust response to a localized domestic threat. A resilient architecture must therefore harden, distribute, and defend the Lower-48 infrastructure that adversarial actors are most likely to access, surveil, disrupt, or attack.

Lower-Latitude and Northern-Tier States Improve Homeland Defense

A lower-latitude architecture, outside of Alaska, concentrated in the northern tier and inland West improves homeland defense in multiple ways.

First, it adds engagement depth. If an incoming threat is detected but not solved by the earliest northern opportunity, inland and northern-tier nodes create successive opportunities for tracking, handoff, decision, and engagement. That is especially important when warning is compressed by maneuvering or low-altitude flight. CBO’s analysis of cruise missile defense and NORAD USNORTHCOM’s posture both point toward wide-area, layered architectures with multiple sensor and engagement zones rather than a single remote line of defense (CBO, 2021; VanHerck Congressional Testimony, 2021).

Second, lower-latitude states sit closer to the sometimes little-known, critical assets being defended. USNORTHCOM has emphasized that homeland defense underwrites the entire U.S. ability to deploy forces overseas and protects citizens, national critical infrastructure, transportation nodes, and leadership. Northern-tier lower-48 states are simply nearer to the dense concentration of military infrastructure, industrial capacity, and urban systems in the continental United States than Fort Greely or Clear are (DoW, 2022; VanHerck, 2021).

Third, they enable space-supported defense more effectively. Homeland defense is moving away from cold-war ballistics dynamics toward persistent tracking from space and robust terrestrial battle management, not just fixed northern radar geometry. MDA and SDA confirmed the February 2024 launch of the first HBTSS prototypes and Tranche 0 tracking satellites. SDA’s Tracking Layer fact sheet states that the architecture is intended to provide global, persistent detection, warning, tracking, and identification of advanced missile threats, including hypersonic systems, and ultimately to incorporate fire-control-quality sensors (MDA & Space Development Agency [SDA], 2024; SDA, n.d.; Fontana et al., 2022).

Fourth, these states are better positioned for sustainment and continuity of operations than remote Arctic nodes. Both DoW and GAO describe Arctic infrastructure and logistics as constrained, while continental strategic installations in the northern tier already sustain large, dispersed, always-on missions. Malmstrom in Montana, F.E. Warren in Wyoming, and Minot in North Dakota each operate large Minuteman III complexes; Cavalier Space Force Station in North Dakota provides missile warning for sea-launched and intercontinental ballistic missiles; and Grand Forks hosts one of SDA’s two operations centers for its proliferated tracking architecture, paired with a mutual-backup site in Alabama. Together, those facts show that the northern tier is already supporting major strategic missions, hardened command functions, communications, and dispersed operations at scale (GAO, 2025; Space Development Agency, n.d.; U.S. Air Force, 2026).

For the inland West specifically, the case is best understood as a planning inference rather than as an assertion about existing missile-defense basing. The interior West and northern tier already host large strategic force and command-support systems. On that basis, Idaho and nearby inland-West locations are logical candidate regions for sensors, command nodes, communications, power resilience, maintenance depots, and potentially future interceptor support because they add depth without continually inheriting a rolling loss of return on investments in Alaska. The Federal Register notice states that the proposed HLD-OTHR systems in the Northwest would provide persistent, long-range early detection of airborne threats that can be obscured from conventional line-of-sight radars by Earth curvature (Air & Space Forces Magazine, 2025; Breaking Defense, 2025; Stars and Stripes, 2025).

The technical significance of these western OTHR sites is that they demonstrate a shift from a point-defense model toward a sensor-and-custody architecture. Over-the-horizon radar uses ionospheric propagation to extend detection beyond the radar horizon, making it relevant to low-altitude cruise missiles and other airborne threats that conventional line-of-sight sensors may detect too late. 

The practical implication is not that Idaho, Nevada, Oregon, Montana, Wyoming, or North Dakota replace Alaska's importance for modern homeland defense against ballistic threats. The American West and northern tier provide the geography for redundant sensing, hardened communications, data fusion, sustainment, and future engagement support in a layered continental missile-defense architecture (Fontana et al., 2022; Gormley, 2003; Scardino, 2021; Wang et al., 2025).

A Robust Architecture is Nationally Distributed 

While Alaska remains a vital component of Arctic homeland defense, the United States should continue to leverage its substantial investments in Alaska’s early warning, long-range discrimination, Arctic operations, and legacy GMD/NGI capacity. Those are mature functions with continuing value, especially for limited rogue-state ballistic threats and for Arctic/NORAD missions (DoW, 2024; U.S. Space Force, 2026). 

Taken as a whole for North America, the priority should be a more agile and wider surveillance and tracking mesh. Canada’s NORAD modernization program is a concrete indicator of where binational defense is heading: Arctic Over-the-Horizon Radar will provide early warning and tracking from the Canada–U.S. border to the Arctic Circle; Polar OTHR will extend surveillance farther north; and Crossbow will add another distributed sensor layer across northern Canada. Canada’s own stated A-OTHR objective is long-range surveillance of the northern approaches to the major population centers in North America. (Department of National Defence Canada, n.d.; Department of the Air Force [DAF], 2025a).

For space-based equities in the lower 48, the United States should accelerate the network that turns warning into custody and custody into fire control. MDA officials identified HBTSS as the space sensor intended to provide fire-control-quality data for advanced missile threats, while SDA’s proliferated architecture provides the global tracking backbone and intentionally distributes operations across states like South Dakota for mission assurance and mutual backup. Architecture such as operations centers, transport and tracking gateways, hardened communications, power resilience, data fusion, and sustainment nodes are critical functions that northern-tier and inland-West states can host (MDA, 2023; MDA & SDA, 2024; SDA, n.d.).

The immediate policy imperative is that future homeland-defense funding should prioritize a continental missile-defense grid consisting of existing Arctic sensors, proliferated space tracking, and dispersed lower-48 nodes for command, communications, sustainment, and potentially additional interception. Concurrently, the USG should support and ensure that fully interoperable Canadian NORAD modernization occurs as soon as possible. While Alaska remains a component of Arctic homeland defense, a much stronger and more sustainable U.S. homeland-defense architecture requires deliberate investment in lower-latitude northern-tier and inland-West states as part of a distributed continental network for unparalleled, enhanced domain awareness and response (DoW, 2024; GAO, 2025; Department of the Air Force, 2025a).

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