A Whole of Nation Approach to Continental Defense
Abstract
The traditional, Alaska-centric U.S. homeland missile defense posture—originally engineered for predictable polar ballistic trajectories—is no longer sufficient. Adversaries have systematically developed hypersonic glide vehicles (HGVs), terrain-hugging cruise missiles (CMs), and Fractional Orbital Bombardment Systems (FOBS) to bypass these northern defenses.
To counter this multi-azimuth, low-altitude, and highly maneuverable threat environment, the United States must buildout a continental distribution of defense capabilities. This “Whole-of-Nation” approach shifts the investment focus from isolated Alaskan installations to a resilient, deeply layered sensor and command network spanning the lower-48 states and leveraging a robust, binational partnership with Canada
A Whole-of-Nation Approach for Arctic Homeland Defense
A regionally centered homeland missile defense posture remains an important component of U.S. homeland defense; however, the threat environment has outgrown it.
The missile defense system in the north was built around a solvable problem. A ballistic missile travels along a known path. The polar trajectory gave defenders time and geometry. Alaska best addressed that threat. The trouble is that adversaries have spent the intervening decades building weapons specifically to invalidate that answer — hypersonic vehicles that maneuver mid-flight, cruise missiles that track terrain below radar line of sight, and reentry systems that compress warnings to the point of irrelevance. The defense infrastructure has not kept pace with what it is now being asked to stop.
The 2022 Missile Defense Review put it plainly — ballistic, cruise, and hypersonic threats together represent an “expanding and accelerating risk” to the homeland, and new long-range missile and space systems have erased the boundary between regional and homeland defense that once made strategic planning simpler.
The FY2024 operational assessment from the Director of Operational Test and Evaluation reinforced the point: the Ground-based Midcourse Defense system has demonstrated capability only against a small number of long-range ballistic threats using simple countermeasures, and only when supported by the full sensor network of the broader Missile Defense System. That is a bounded capability operating in an unbounded threat environment.
A Changing Threat Geometry
The Alaska-first design was built for a threat environment defined by predictable polar or North Pacific ballistic trajectories. That assumption no longer holds. What the National Air and Space Intelligence Center’s own threat assessments show is a weapons environment that has methodically outpaced Cold War intercept geometry. Hypersonic glide vehicles fly lower and faster than ballistic missiles and maneuver across every phase of flight. The northern sensor and interceptor network was built based on predictable physics. These weapons operate outside those predictions.
Published research has been running the numbers on this for some time. Fontana, d’Errico and Di Vito identified what actually degrades long-range missile defense as threats evolve: radar-horizon cutoffs, gaps in sensor coverage and tracking discontinuities that feed on each other. Lee et al. looked specifically at low-altitude maneuvering flight and found that the margins interceptor systems require — detection windows, reaction time — do not hold up against it.
Fractional Orbital Bombardment Systems cut at the problem from a different angle. The DIA’s 2024 Nuclear Challenges report describes a FOBS as a weapon that orbits and comes around from the south — over the South Pole — because that is precisely where U.S. early-warning networks are not looking. A sensor grid optimized for northern approaches cannot cover what is coming from the opposite direction.
Cruise missiles do not fit the Alaska model, and the Congressional Budget Office (CBO) said so plainly: ballistic intercept systems built for high-altitude engagements have no useful application against weapons that fly low, hug terrain, and approach from any direction. Defending against them means sensors, shooters, and command capacity threaded through the defended territory — not one site in the Alaskan interior making coverage claims it cannot back up.
According to a 2023 Missile Defense Agency (MDA) briefing, Russian and Chinese platforms — aircraft, submarines, surface ships and ground launchers — already cover every launch vector. The threat does not come from one direction.
General VanHerck’s 2021 testimony identified what the defense must be: layered, distributed, running from the seabed to space. Four years on, Guillot kept that framing and reduced it to its operational core: you cannot defeat what you cannot see. What neither officer mentioned in describing that requirement was Alaska.
These challenges are further reinforced by the emerging recognition within U.S. Government policy documents that the threat has diversified in azimuth, not just capability. The 2022 Missile Defense Review states that adversaries are integrating more advanced missile capabilities into their strategies and that new long-range missile and space systems have clear implications for both regional and homeland defense.
A separate 2023 MDA budget briefing explained that hypersonic missiles present a new challenge because they travel at exceptional speeds with unpredictable flight paths. Adversaries have also shown sustained interest in Arctic academic research — the kind that maps vulnerabilities, identifies sensor gaps, and informs where existing defenses can be exploited. That is not a reason to abandon the northern network. It is one more reason not to make it the only thing standing between the threat and its target.
Alaska’s Role and Its Limits
How is this achieved? The Long-Range Discrimination Radar at Clear Space Force Station recently achieved operational acceptance and provides critical search, tracking, and discrimination capability in support of GMD fire control. The FY2025 defense budget overview continues Next Generation Interceptor (NGI) development, targeting a deployed fleet of 64 interceptors by decade’s end. These are mature investments with real value against the bounded threat set they were designed to address — primarily limited rogue-state ballistic missile attacks from North Korea and Iran.
The mission GMD was built for in 2004 was real and finite. What has happened since is that the threat surrounding that mission kept growing — in speed, in altitude, in the directions it arrives from. The 2024 DoD Arctic Strategy acknowledges the sensor and air-defense gaps in the Arctic while making clear the solution runs well beyond Alaska — it involves sensing networks, communications, allied systems, and space-based capabilities working together. The department does not frame this as an Alaskan problem. It frames it as a national one.
The Government Accountability Office (GAO) put numbers to what Alaska actually costs to operate: infrastructure that falls short, logistics that strain under routine demand, maintenance expenditures that outpace what comparable continental missions require. The 2024 Arctic Strategy acknowledged the same basic reality — the North American Arctic is short on roads, ports, and communications, compared to the European Arctic.
Fort Greely is 100 miles from Fairbanks and roughly 3,000 miles from the cities, bases, and defense plants it exists to protect. Clear Space Force Station is not meaningfully closer to anything that matters — no coastline, no major logistics hub, no rapid reconstitution capacity within reach. When something breaks at either installation, fixing it is an expedition.
The case for Alaska is not gone. The case for sending the next round of critical investment there is. Fast repair, backup systems, communications that survive pressure, the ability to scale — the mission requires all of it now. Alaskan geography delivers none of it well.
The Case for Continental Distribution
Lose the northern intercept window and distributed nodes keep working — tracking, decision chain open, another engagement possible. Lose it with everything concentrated in Alaska, and there may be nothing left to work with. Hypersonic and terrain-hugging cruise missiles were not designed to beat every layer of a distributed defense. They were designed to beat the first one fast enough that no other layer has time to matter. Fortunately, there are at least five critical reasons that a continental distribution of capabilities provides layered protection.
This is the first advantage of continental distribution: engagement depth. The CBO’s cruise missile defense analysis and the North American Aerospace Defense Command (NORAD) and United States Northern Command (USNORTHCOM) posture both point the same direction: multiple engagement zones distributed across the defended area. Not one chokepoint at the top of the map.
Second, lower-latitude states sit closer to the assets being defended. USNORTHCOM has emphasized that homeland defense underwrites the entire U.S. ability to deploy forces overseas and protects citizens, critical infrastructure, transportation nodes, and leadership. The 2022 Missile Defense Review commits to examining “active and passive defense measures to decrease the risk from any cruise missile strike against critical assets, regardless of origin.” The Northern Tier lower-48 states are closer to the dense concentration of military infrastructure, industrial capacity, and urban systems than Fort Greely or Clear.
Third, the February 2024 launches, which delivered capabilities to orbit oriented towards different threat vectors, were a signal worth reading carefully. Hypersonic Ballistic Tracking Space Sensor (HBTSS) prototypes and Tranche 0 satellites had nothing to do with extending northern radar reach. Persistent orbital tracking, full flight path custody, subsequent tranches built around low-latitude coverage, none of that follows the logic the Alaskan ground-radar network was designed around. The fielded and legacy systems share a mission. They do not share assumptions.
Fourth, it is critical to notes that a fixed northern complex also has a fixed address. Anyone planning to suppress U.S. missile defense knows where the nodes are and roughly what it would take to hit them. That is a workable problem for an adversary. Push those same functions out across continental geography — more sites, harder to find, no single action that brings the network down — and it stops being workable the same way. The 2025 DoD testimony called for a single integrated multi-layer defense. That is not a description of one location.
Fifth, the northern tier already does this kind of work. Malmstrom in Montana, F.E. Warren in Wyoming, Minot in North Dakota — all sustain large, dispersed strategic nuclear complexes. Cavalier Space Force Station in North Dakota covers sea-launched and intercontinental ballistic missile warning. Grand Forks runs one of the Space Development Agency’s two operations centers for its proliferated tracking network, backed by a mutual-support site in Alabama. The argument for these states is not hypothetical. The missions are already there.
The Over-the-Horizon Radar Signal
The most concrete indicator of where investment is heading is the Department of the Air Force’s Homeland Defense Over-the-Horizon Radar (HLD-OTHR) environmental impact statement, filed in April 2025. The notice states that 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.
Stars and Stripes disclosed that three locations in Oregon and one each in Idaho and Nevada had been selected as potential sites. Breaking Defense reported that the Air Force is scouting three western states for the new system. Air & Space Forces Magazine reported that the first two systems are planned for Oregon and will be capable of detecting inbound threats from up to 4,000 nautical miles away.
The ionosphere reflects high-frequency signals toward Earth at ranges conventional line-of-sight radar cannot touch. That is what makes over-the-horizon systems relevant to cruise missiles and low-altitude threats — the ones that get under standard radar and stay there until the engagement window is nearly gone. Oregon, Idaho, Nevada — these sites are not Alaska with a different zip code. They are closing a different gap, one that has existed since the defense was first built around ballistic geometry.
Canada and the Binational Dimension
The United States and Canada partner to defend North America. Canada’s NORAD modernization program aligns with U.S. continental investment and is now moving from commitment to construction. Backed by a $38.6 billion, 20-year investment announced in 2022, the Department of National Defense Canada is fielding three interlocking surveillance layers: the Arctic Over-the-Horizon Radar (A-OTHR), providing early warning and threat tracking from the Canada-U.S. border to the Arctic Circle; the Polar OTHR, extending surveillance farther north across the Canadian Arctic Archipelago and beyond; and Crossbow, a joint Canada-U.S. classified network of sensors distributed across northern Canada, expected to be operational by 2029-2030.
The A-OTHR itself is adapted from Australia’s Jindalee Operational Radar Network — a $4 billion acquisition representing Australia’s largest-ever defense export — with an initial operating capability targeted for December 2029. Canada’s stated objective for the program is long-range surveillance of the northern approaches to major North American population centers, and successive NORAD commanders have described the existing radar network as no longer sufficient to detect or deter threats from a resurgent Russia and rising China.
Modernization in Canada that is fully interoperable and moving rapidly would significantly expand the surveillance perimeter. This should be pushed by Washington not as a matter of alliance management or diplomatic goodwill, but because it is detrimental to the continental defense picture if it is not done.
A National Industrial and Strategic Asset
Continental distribution has an industrial logic that the military geometry argument tends to crowd out. The intercept is the visible part. Behind it sits everything that makes a sustained defense possible — shipyards in Maine and Texas keeping the fleet operational, steel coming out of Ohio and Pennsylvania, propulsion systems built in Michigan and Wisconsin, space operations running out of Colorado and California. Remove any of those and what remains in Alaska cannot function for long.
Washington, Oregon, Massachusetts, and Texas maintain the fleet in service. The Great Lakes states supply what Arctic readiness actually runs on — heavy equipment, steel and manufacturing capacity that the mission consumes faster than it can be replenished. Getting from raw sensor data to a commander’s decision runs through California, Virginia, Florida, New Mexico, and Colorado: space operations, intelligence fusion, cyber defense.
Then there is the inland West. North Dakota, Montana, Wyoming, Idaho, Utah, Colorado, Nevada — this corridor already hosts missile sensing, nuclear deterrence infrastructure, air mobility, space integration, and the basing depth that long-range defense requires. These are not candidate states for future missions. They are running them now. The Sentinel groundwork at Malmstrom, which began in April 2026, is one data point in a much longer list.
Homeland missile defense investment in this geography is not a construction project. The foundations are already poured. What is missing is the deliberate decision to build on them.
The Policy Imperative
Alaska’s early-warning systems, its discrimination radar, its GMD and NGI infrastructure — none of that should be walked away from. These are working investments with real mission value. What needs to change is where new money goes. The priority should be a continental grid: Arctic sensors feeding into proliferated space tracking, with command, communications, sustainment, and intercept nodes distributed across the lower 48 states.
The sabotage dimension makes this more urgent than it might otherwise appear. The infrastructure that actually runs U.S. homeland defense — the warning systems, the tracking networks, the command-and-control chains, the logistics that move people and equipment — lives overwhelmingly in the continental United States. An adversary that wants to degrade American defense performance does not need to reach a remote installation in interior Alaska. Small teams, drone operators, cyber actors, insider threats — they can hit power grids, communications nodes, transportation chokepoints, defense-industrial facilities. The damage lands the same way.
Guard units, state law enforcement, emergency managers, federal protective services, commercial utilities — these are the people and organizations that show up when something in the defense enterprise breaks or gets hit. They are distributed across the continental United States. Alaska has very little of it. Stacking more critical functions there does not improve the defense. It just puts more of it somewhere the recovery capacity cannot reach quickly.
As the DOT&E’s FY2024 assessment made clear, GMD’s demonstrated capability is already bounded by the sensor architecture supporting it — which makes the resilience of that continental support infrastructure not a secondary concern, but the primary one. This means investment in the northern tier, inland West, Great Lakes, and Northeast not just strategically sound but urgently necessary. Arctic defense is not an Alaskan problem. It is a continental one. American policy, investment, and military posture need to reflect that reality.
