The Precision Mirage: What Happens When GPS-Guided Weapons Meet Systematic Jamming
Western militaries built three decades of doctrine around satellite-guided precision. Russia and China built their counter-strategies around denying it. The weapons still work—but the advantage they promised is eroding faster than the modernization meant to restore it.
The Precision Mirage
For three decades, Western militaries have built their way of war around a single assumption: that satellites will always whisper coordinates to weapons. The assumption is now under systematic assault.
Russia’s electronic warfare units in Ukraine have demonstrated what Pentagon planners long feared but rarely tested: GPS denial at scale. American-supplied Excalibur artillery shells, once celebrated for hitting targets within two meters, saw their accuracy degrade by 50% or more when Russian jamming intensified in 2023. Ukrainian forces adapted by switching to cheaper unguided munitions—not because they preferred them, but because precision had become a lie their weapons could no longer tell.
This is not a Ukrainian problem. It is a preview. The Western military advantage built on precision-guided munitions faces a structural challenge that no software update can fix. When adversaries can systematically deny GPS across entire theaters of operation, the weapons designed to minimize casualties and maximize efficiency become expensive approximations of the dumb bombs they replaced. The question is not whether this vulnerability exists—that debate ended somewhere over the Donbas—but what happens to military strategy when the foundation cracks.
The Architecture of Dependency
The scale of Western reliance on GPS defies casual comprehension. The Department of Defense defines precision-guided munitions as weapons using “radio signals from the global positioning system (GPS), laser guidance, and inertial navigation systems (INS)” to achieve accuracy “to reportedly less than 3 meters.” This definition contains its own vulnerability: GPS appears first because GPS comes first. The other systems are backups.
Consider the weapon that defined American air power in the post-Cold War era. The Joint Direct Attack Munition—JDAM—converts unguided bombs into precision weapons through a GPS/INS guidance kit. Over 500,000 have been produced. They cost roughly $25,000 each, transforming $2,000 gravity bombs into weapons that can strike within three meters of their targets. The economics seemed irresistible: why drop ten bombs hoping one hits when you can drop one bomb knowing it will?
This logic cascaded through every acquisition decision for a generation. HIMARS rockets use GPS for precision targeting. Excalibur shells rely on GPS for their vaunted accuracy. Tomahawk cruise missiles, though equipped with terrain-matching systems, use GPS for mid-course corrections. The F-35’s targeting systems assume continuous satellite access. Even ground forces navigate with GPS-enabled Blue Force Trackers that distinguish friend from foe.
The dependency runs deeper than weapons guidance. GPS provides timing signals that synchronize communications networks, coordinate logistics, and enable the data fusion that gives Western forces their information advantage. Lose GPS and you lose more than accuracy. You lose coherence.
The Defense Science Board warned in May 2024 that “the availability and accuracy of GPS and Global Navigation Satellite Systems (GNSS) may not be guaranteed at all places and times.” This understates the problem. Russia and China have not merely developed the capability to deny GPS—they have integrated electronic warfare into their operational concepts as a first-order priority.
Russian electronic warfare systems like the Krasukha-4 can jam GPS signals across hundreds of kilometers. Chinese capabilities remain less documented but are assessed as equally formidable. Both nations have observed Western operations for decades, identifying the single point of failure that enables American military dominance. They have built their counter-strategies around exploiting it.
The physics favor the jammer. GPS satellites transmit at roughly 25 watts from 20,000 kilometers altitude. By the time those signals reach Earth, they are extraordinarily weak—weaker than the background noise of a typical urban environment. Overwhelming them requires only watts to kilowatts at tactical distances. The energy asymmetry is stark: the constellation cost billions to deploy and maintain; effective jamming costs thousands.
The Degradation Cascade
What happens when precision fails? The immediate effects are obvious: weapons miss. The second-order effects are more corrosive.
Precision weapons justified themselves through efficiency. A single JDAM could destroy a target that once required dozens of unguided bombs. This meant fewer sorties, fewer aircraft, fewer pilots at risk, smaller logistics tails. It also meant smaller stockpiles seemed adequate. Why maintain Cold War inventories when each weapon does the work of ten?
The Congressional Research Service documented that American forces “became reliant on precision-guided munitions to execute military operations.” This reliance shaped everything from doctrine to budgets to industrial capacity. The United States produces roughly 240,000 artillery shells annually—barely 40 days of Ukrainian consumption at current rates. The assumption was always that precision would substitute for volume.
When GPS denial forces reversion to unguided munitions, the math inverts. Suddenly you need ten weapons instead of one. But the stockpiles weren’t built for that. The factories weren’t built for that. The logistics chains weren’t built for that. The training wasn’t built for that.
Here lies the deeper problem. The skills required to employ unguided weapons effectively have atrophied. Artillery crews trained to call in GPS-guided Excalibur rounds lack the expertise their predecessors developed in calculating ballistic solutions manually. Pilots who have never dropped a dumb bomb in combat must suddenly rediscover techniques their service abandoned as obsolete. The institutional knowledge exists in manuals. It does not exist in muscle memory.
Research on heritage craft skills reveals that expertise dies not from lack of documentation but from lack of continuous practice communities. The same pattern applies to military capabilities. You cannot simply read a manual and recover what took decades to develop. The Navy reinstated celestial navigation training in 2016 after a decade-long gap—but the tacit knowledge infrastructure that made such training effective had partially dissolved. Explicit documentation cannot transmit what continuous practice embeds.
This creates a capability gap that money cannot quickly close. Even if factories surge production of unguided munitions, even if stockpiles are rebuilt, the human capital required to employ them effectively requires years to reconstitute. GPS dependency has restructured not just weapons but minds.
The Modernization Mirage
The obvious response—make GPS harder to jam—has been underway for years. It has also been failing.
The M-code signal, designed to be more resistant to jamming and spoofing, was supposed to reach operational capability years ago. It has not. The Director of Operational Test and Evaluation reported in 2024 that “ongoing development delays of the Next Generation Operational Control System (OCX) and the Military-Code (M-code) GPS User Equipment (MGUE) program schedules are continuing to delay the U.S. Space Force’s GPS-modernized civil, M-code, and navigation warfare functions.” These delays, the report concluded, “put U.S. and allied warfighters at risk.”
The ground control system has become a case study in acquisition dysfunction. OCX was originally scheduled for delivery in 2013. Block 0 arrived in 2017. Blocks 1 and 2 remain in development. Each delay compounds the next: the teams that designed the original architecture rotate out, taking institutional knowledge with them. New teams inherit fictional timelines and create new fictional timelines to replace them.
Meanwhile, the user equipment that would actually employ M-code signals remains chronically underfunded. The GPS III satellite program received severe budget cuts—83% reduction in one fiscal year—to fund OCX fixes. The space segment advances; the ground segment lags; the user equipment that would make either useful remains “approaching final tests” after years of delays.
This is not mere bureaucratic dysfunction. It reflects a deeper structural problem: the acquisition system optimizes for what it can measure (contract milestones, budget execution rates) rather than what matters (operational capability delivery). Each program manager inherits optimistic projections from predecessors and generates new optimistic projections for successors. The planning fallacy compounds across generations.
The result is a modernization effort that perpetually promises resilience while delivering vulnerability. Forces train for GPS-denied environments using equipment that cannot actually operate in GPS-denied environments. The exercises validate doctrine without validating capability. They perform the ritual form without the sacramental substance.
The Alternative Landscape
If GPS cannot be made sufficiently resilient, what alternatives exist?
Inertial navigation systems provide position information without external signals. But they drift. A high-quality INS might accumulate errors of one nautical mile per hour of operation. For a weapon in flight for minutes, this is manageable. For a ground force navigating for days, it is not. INS can bridge GPS gaps; it cannot replace GPS.
Terrain-matching systems like TERCOM compare sensor readings against stored digital maps to determine position. They work—when the terrain has sufficient features to match, when the databases are current, when the enemy hasn’t modified the landscape. They shift the vulnerability from real-time signals to pre-mission data integrity. Different failure mode, similar fragility.
Celestial navigation works when the sky is visible and the operator is trained. Neither condition is guaranteed in combat. The Navy’s reintroduction of celestial training addresses a gap but not the gap.
eLORAN—enhanced Long Range Navigation—offers a terrestrial alternative using powerful ground-based transmitters that are far harder to jam than satellite signals. But eLORAN infrastructure was largely dismantled after GPS made it seem obsolete. Rebuilding it requires years and billions. The United States has studied eLORAN restoration repeatedly. It has not funded eLORAN restoration meaningfully.
Galileo, the European GNSS, offers some redundancy for military users with access to its encrypted Public Regulated Service. But Galileo’s governance structure—operated by the EU collective rather than a single nation—creates command-and-control ambiguities that military planners find uncomfortable. The constellation helps; it does not solve.
Each alternative addresses part of the problem while introducing new vulnerabilities. The honest assessment is that no single system can replace GPS, and the multi-system architectures that could provide genuine resilience remain largely conceptual.
The Strategic Reckoning
What does this mean for Western military advantage?
The precision-strike paradigm enabled a particular theory of victory: that technological superiority could substitute for mass, that quality could defeat quantity, that small professional forces could prevail against larger adversaries through superior accuracy and information. This theory shaped force structure, acquisition priorities, alliance commitments, and deterrence strategies for three decades.
Under systematic GPS denial, the theory fractures. Not completely—precision weapons retain some capability through backup systems, and not all adversaries can generate theater-wide denial. But the margin of advantage narrows dramatically. The assumption that Western forces can strike with impunity while adversaries cannot becomes untenable when both sides face similar accuracy constraints.
This has cascade effects through military planning. If precision weapons require more volume to achieve effects, logistics requirements expand. If logistics requirements expand, deployment timelines lengthen. If deployment timelines lengthen, adversaries gain time to consolidate gains. The speed advantage that precision was supposed to provide may reverse.
The alliance implications are equally significant. NATO’s conventional deterrence in Europe rests partly on the assumption that precision-strike capabilities can offset Russian numerical advantages. If GPS denial degrades those capabilities substantially, the conventional balance shifts. This does not mean NATO cannot defend its territory. It means the defense becomes costlier, slower, and less certain.
In the Pacific, the calculus is starker. Operations across the vast distances of the Western Pacific depend on precision weapons to generate effects from limited platforms. Carrier strike groups cannot simply surge more aircraft; the deck space is fixed. If each aircraft requires more sorties to achieve the same effects, the operational math changes fundamentally.
The Path Not Taken
Three intervention points could alter this trajectory. None is easy.
First, alternative PNT investment at scale. The United States could commit to rebuilding eLORAN infrastructure, developing quantum navigation systems, and fielding multi-constellation receivers that can exploit GPS, Galileo, GLONASS, and other signals simultaneously. The technology exists or is maturing. The funding does not. This would require shifting billions from other priorities over a decade—a political decision that no constituency actively demands.
Second, doctrine and training transformation. Forces could train extensively with degraded or denied GPS, developing the skills and tactics to operate effectively when precision fails. This means accepting worse performance in exercises, which conflicts with the institutional incentive to demonstrate success. It means investing in training infrastructure that simulates realistic electronic warfare environments. It means promoting officers who excel at adaptation rather than optimization.
Third, industrial base restructuring. The munitions industrial base could be rebuilt to produce both precision and unguided weapons at scale, maintaining the capacity to surge either depending on operational conditions. This requires sustained investment in production lines that may sit idle during peacetime, accepting inefficiency as the price of resilience. Current defense economics punish such redundancy.
Each intervention requires accepting costs today for benefits that may never be tested. Each conflicts with institutional incentives that reward short-term efficiency over long-term resilience. Each demands political will that has been absent for decades.
The most likely scenario is therefore continued drift: incremental modernization that perpetually lags the threat, exercises that validate doctrine without capability, and strategic assumptions that grow increasingly disconnected from operational reality. The vulnerability will be addressed—after it is exploited.
What Remains
The precision revolution transformed warfare. It also created a dependency that adversaries have learned to exploit. The Western military advantage built on GPS-guided weapons is not disappearing, but it is eroding—and the erosion accelerates as electronic warfare capabilities proliferate.
The response required is not technical but strategic: accepting that precision is a capability, not a guarantee, and rebuilding the capacity to fight when it fails. This means stockpiles, skills, and systems that do not assume satellite access. It means industrial capacity that can surge unguided munitions. It means doctrine that treats GPS denial as the expected condition rather than the edge case.
None of this is happening at the necessary scale. The bureaucratic incentives point elsewhere. The political attention focuses elsewhere. The budgets flow elsewhere. And so the gap between assumption and reality widens, year by year, until the assumption is tested.
When that test comes, the forces that prevail will not be those with the most sophisticated weapons. They will be those that can still fight when the satellites fall silent.
Frequently Asked Questions
Q: Can GPS jamming actually affect precision weapons in combat? A: Yes, and it already has. Ukrainian forces reported significant accuracy degradation in GPS-guided Excalibur shells when Russian jamming intensified. The weapons didn’t become useless, but their precision advantage—the entire reason for their cost—diminished substantially.
Q: Why can’t the military just use backup navigation systems? A: Backup systems like inertial navigation help but cannot fully substitute. They drift over time, accumulating errors that GPS normally corrects. A weapon in flight for minutes can tolerate this drift; forces operating for days cannot. The backups bridge gaps rather than fill them.
Q: How long would it take to fix GPS vulnerability? A: The M-code upgrade designed to improve jamming resistance has been delayed for over a decade and remains incomplete. Even with adequate funding, fielding resilient systems across the force would require five to ten years. The vulnerability is structural, not merely technical.
Q: Does this mean precision weapons are obsolete? A: No, but their advantage is conditional rather than absolute. Against adversaries without sophisticated electronic warfare, precision weapons retain their effectiveness. Against peer competitors with systematic GPS denial capability, the advantage narrows considerably.
Sources & Further Reading
The analysis in this article draws on research and reporting from:
- Congressional Research Service on Precision-Guided Munitions - Comprehensive overview of PGM technology, costs, and congressional considerations
- Defense Science Board Report on PNT Control - May 2024 assessment of GPS vulnerabilities and recommendations
- DOT&E FY2024 Annual Report on GPS Enterprise - Operational testing assessment of GPS modernization delays
- Army Acquisition Support Center on System-of-Systems Integration - Analysis of complex system interdependencies
- Army Science Board on Defense Munitions Industrial Base - Assessment of surge capacity constraints
- Modern Diplomacy on Electronic and Counter-Space Warfare - Overview of Russian and Chinese EW capabilities
- JAPCC on Electronic Warfare - NATO perspective on EW as operational discipline
