Part One · Northern Dipper
For twelve days in June 2025, Iran and Israel fought the region's heaviest direct missile exchange between states. Iran fired roughly 550 ballistic missiles (Fattah-1 hypersonics, Kheibar Shekans, Sejjils) and more than a thousand drones. The target list ran from Israeli airbases (Nevatim, Ramat David, Tel Nof) to Tel Aviv, Soroka Hospital in Beersheba, and the American base network from Al Udeid and Al Dhafra to Ain al-Asad. Most never arrived where they were aimed.
The interceptor batteries were the defense the cameras could see. The quieter work was electronic. American jamming aircraft over the Gulf (among them Navy EA-18G Growlers flying off the Carl Vinson) were not attacking Iranian radar; they were attacking the missiles' sense of position, flooding the open civilian GPS frequency, the L1 band at 1575.42 MHz, with enough noise to drown the signal out. Regional reporting put the GPS-guidance failure rate on Iranian missiles above seventy percent. The weapons fell back on inertial guidance, drifted kilometers in flight, and buried themselves in open desert.
Three weeks after the ceasefire, Iran's communications ministry confirmed what the war had suggested: some of the GPS disruption over Iran had been Tehran's own defensive jamming, and the Islamic Republic would pursue China's BeiDou as the alternative. The IRGC changed receivers. By the time the next war opened, per regional reporting, Iran's missile units were on BeiDou's restricted B3A channel: a Chinese military signal at 1268.52 MHz, encrypted and outside the L1 band being jammed. Access came through the 25-year China–Iran Comprehensive Strategic Partnership signed in 2021. The L1-band denial that the United States had counted on since Desert Storm (the workhorse RF attack against unencrypted GPS) no longer worked.
Eight months later they fought again, and the jamming was heavier. Within twenty-four hours of the opening strikes more than 1,100 ships across the Gulf reported their navigation scrambled; more than twenty jamming clusters were operating between the Strait of Hormuz and the Gulf of Oman. In the first war, Iranian guidance reliability (the share of missiles reaching their aimpoints within design accuracy) had collapsed. This time, under heavier jamming, reports put it near 98 percent. The miss-distance shrank — strikes that had drifted into open desert were now reaching the bases and structures they were aimed at. On 3 March a Kheibar Shekan punched into Al Udeid, the largest American base in the region. Alain Juillet, former director of the DGSE, France's foreign-intelligence service, said it in one phrase: Iranian strikes had become "much more accurate."
Most of what the camera could see was unchanged: the sky, the jammers, and the airframes were similar in both wars. The most legible variable to shift was the receiver. Other things almost certainly moved too (tactics, learning, defensive posture, mission planning), but the receiver is the change a strategist can point at. Iran had stopped navigating by the American satellite system, GPS, and switched to the Chinese one, BeiDou (北斗, Běidǒu — the Northern Dipper).
The Iran-Israel exchange is not the only place this kind of contest is visible. Russian forces in Ukraine routinely defeat GPS-guided American munitions with electronic warfare; Israel has used spoofing against Iranian drones; the air war over Kashmir, six weeks earlier, ran along similar systemic lines. The Gulf in 2026 is one frame in a longer film.
Iran's salvo is airborne. Five hundred-plus ballistic missiles over the next twelve days (Fattah-1, Kheibar Shekan, Sejjil) at Israeli airbases, Tel Aviv, the Gulf base network.
An EA-18G works GPS L1 at 1575.42 MHz. This is not missile defense in the cinematic sense — it is just enough RF energy to drown the satellite signal out.
The satellite fix drops and inertial guidance takes over. Every minute without a GPS correction turns precision into drift.
Eight months later the missiles are reaching their targets, even though the aircraft and the jamming on either side are unchanged.
The receiver changed. Iranian guidance had moved onto BeiDou's restricted B3A channel. L1 noise does not kill B3A; the fight moves to another band, against a signal the jammer can bury only by brute force and geometry.
These two wars are lessons in how the character of war is changing. The American military and its strategic doctrine were built around decisive battle, settled by exquisite platforms (the carrier, the stealth fighter, the precision-guided weapon) in one or two pivotal engagements. That era is closing. What is opening is sustained attrition, where the country that can produce cheap precision in volume, replace it after losses, and bind it together across weapons, sensors, and communications outlasts the country that brought the more expensive instrument to a single fight. At the center of that integration sit the satellites the rest of it depends on. To see how a war can turn on them, begin with what they actually do.
Part Two · What GPS actually is
A GPS receiver doesn't transmit anything. It listens. Thirty-one satellites are circling the earth twenty thousand kilometers up, and each one is doing the same simple thing on a continuous loop: broadcasting the time on its onboard atomic clock and its own position in orbit. The signal is faint (by the time it reaches a ground antenna it arrives below the noise floor of the receiver), but those two pieces of information are all the receiver needs.
From the time the satellite said the signal was sent and the time the receiver heard it, the receiver knows how long the signal took to arrive. Multiply by the speed of light: that's the distance to the satellite. Almost. The receiver's clock is a cheap quartz oscillator, not atomic, and it drifts. Every "distance" the receiver computes carries the same clock error baked into it. The technical name for this not-quite-distance is a pseudorange.
One satellite gives you a distance, which puts you somewhere on a sphere around it. Two satellites narrow you down to the circle where their two spheres intersect. A third sphere reduces that circle to two possible points; in practice one is on Earth and the other is out in space, and the receiver picks the sensible one. That's trilateration. The catch is that your receiver's clock was wrong by some unknown amount, so all three "distances" are slightly off, and the three spheres don't actually meet cleanly. A fourth satellite gives the receiver enough information to solve for the clock error and the position at the same time. Four measurements, four unknowns: three position coordinates and the clock error. They come out together. Your phone learns where it is and what the correct time is in the same instant. The cheap quartz oscillator doesn't become atomic — it borrows atomic time from orbit.
Thirty-one GPS satellites circle the earth, each one constantly broadcasting two things: the current time on its atomic clock, and its position in orbit. They don't know who is listening. The receiver does all the math.
A signal from one satellite arrives. The receiver knows when the satellite said it was sent and when its own clock says it arrived. The trip took about 70 milliseconds. Multiplied by the speed of light: the satellite is roughly 21,000 km away.
Knowing you're 21,000 km from this satellite means you're somewhere on a sphere of that radius, centered on the satellite. Anywhere on the sphere. One satellite isn't enough to find you.
A second satellite gives you a second distance and a second sphere. The two spheres intersect in a circle. You're somewhere on that circle, and two satellites aren't yet enough to tell where on it.
A third satellite, a third sphere. The third sphere cuts the circle to two points; in practice one is on Earth and the other is out in space, and the receiver picks the sensible one. Three satellites, one location. This is trilateration.
Every distance you computed is slightly wrong, because your phone's clock isn't atomic — it's quartz, and it drifts. The same clock error contaminates every measurement equally. The three circles don't quite meet at one point: they all expand or shrink together as the clock error grows or shrinks. There's one value of clock error that would make them meet cleanly. You don't know what it is yet.
A fourth satellite gives the receiver the missing piece. Four measurements, four unknowns: your three position coordinates and the clock error. The math solves them all at once. Your phone learns where it is and what time it is in the same instant.
That is the whole architecture: pseudoranges, geometry, four unknowns solved against four equations. GPS and BeiDou run on the same fundamentals: same math, same trilateration, same solve. Where they diverge is in everything wrapped around that shared core: where the satellites sit in orbit, how many layers each system flies, what signals each chooses to broadcast, what protections those signals carry, and which users get access to which tier.
Part Three · The precision revolution
The capability those satellites deliver has a name: PNT, for positioning, navigation, and timing. Positioning is where you are. Navigation is how to get to where you're going. Timing is the least obvious of the three and the most important: a single shared clock is what lets scattered units and machines act as one instead of separately. PNT is what turns a satellite signal into a guided weapon.
It is worth remembering how recent precision is. Between 1965 and 1972, American aircraft flew 871 missions against one bridge in North Vietnam, the Thanh Hoa, and lost eleven planes. The bridge stayed up. Iron bombs simply did not land where they were aimed. In April and May 1972, F-4 fighters returned with the first practical laser-guided bombs and brought the bridge down in two strikes. Laser guidance worked, but it needed clear weather and a human operator keeping the target in view. Smoke or clouds, and the bomb lost the spot.
GPS removed both restrictions. A weapon that knows its own position can fly to a set of coordinates in any weather, day or night, without ever seeing what it hits. A 1943 B-17 landed bombs within about 1,200 feet (370 m) of where they were aimed half the time. Laser-guided bombs in the 1991 Gulf War landed within roughly 30 feet (10 m). A GPS-guided JDAM today lands within about 16 feet (5 m). PNT made that last leap, from tens of feet to a few meters. PNT is also why the leap is fragile. Jam the satellite signal and the weapon falls back on its own internal guidance, with the error growing from a few meters to tens of meters, the difference between the building and the block.
A B-17 dropping from 25,000 feet (7,600 m) landed half of its bombs within about 1,200 feet (370 m) of where it was aimed. The other half landed farther out, sometimes far enough out that they hit the next neighborhood. To destroy one factory, you had to bomb the city around it.
This is an F-105D Thunderchief over North Vietnam, with iron bombs slung beneath its wings. Over seven years, American aircraft flew 871 missions against the Thanh Hoa Bridge, lost eleven planes, and never brought it down. Unguided bombs simply did not land where they were aimed.
This is the Thanh Hoa Bridge after F-4 fighters arrived carrying the first practical laser-guided bombs. They dropped it in a single strike. Laser guidance worked, but it depended on clear weather and a human operator keeping a laser dot on the target. Smoke or clouds, and the bomb lost the spot.
Laser-guided bombs landed within roughly 30 feet (10 m) of where they were aimed, when weather and visibility cooperated. The ratio reversed: one weapon could destroy one target, instead of thousands of bombs being needed to take out one factory.
A modern GPS-guided JDAM lands within about 16 feet (5 m) of where it was aimed. The weapon is no longer the source of error. The error is in whatever coordinate you gave it.
The accuracy revolution did something else at the same time. It detached precision from the weapon. A guided bomb is only as accurate as the coordinate that aims it. A 16-foot bomb sent to the wrong location is a wrong-location miss. The work slid off the weapon and onto the web that finds, names, and steers it. In 1998, two American officers, Vice Admiral Arthur Cebrowski and John Garstka, gave the shift its name in the Naval Institute's Proceedings: war was moving from platform-centric to network-centric, and the advantage would no longer live in any one machine but in how tightly all of them were wired together.
Break any link (sensor, network, PNT, or weapon) and the most expensive bomb in the world lands on empty ground.
We caught a glimpse of the systems competition in the open on 7 May 2025. India and Pakistan fought the largest air battle in decades. India flew the Rafale, a French jet near the top of what fighters can be, relying largely on its own sensors and missiles. Pakistan flew the J-10C, a cheaper Chinese export, inside an integrated kill chain: a Swedish Saab Erieye carrying the air picture, a Pakistani Link-17 datalink handing targets to silent-running J-10Cs, BeiDou for navigation, and the long-range PL-15 missile, which per Indian accounts after the engagement was fired from past the distance their pilots had expected to face. Some accounts claim Pakistan fired the domestic PL-15, drawn from PLA stockpiles, rather than the export-spec PL-15E it had previously bought. If true, the detail matters more than the range: China has historically armed customers only with downgraded export variants, never from its own inventory. Handing a partner the real missile on the eve of a fight would be new. At least one Rafale came down. The lesson was not about airplane quality but about the chain each side was operating inside. For most of the era since 1991, integration of that kind was something a rival could only buy from the United States, packaged whole and on American terms. What China changed is that it started selling the components (fighter, sovereign navigation, long-reach missile) at prices that let a state without American patronage wire its own chain. And several of those 'components' are themselves integrated systems: BeiDou alone arrives as a stack with navigation, messaging, signed signals, and layered orbits already wired together, doing much of the chain-building for the buyer.
- SENSOR
- onboard radar only
- NETWORK
- — isolated —
- PNT
- GPS, contested
- WEAPON
- MICA
- SENSOR
- Saab Erieye AEW&C
- NETWORK
- Link-17 (Pakistan)
- PNT
- BeiDou
- WEAPON
- PL-15/E
The exquisite weapon still matters. But it has become the last link in a chain, and a chain is only as strong as its weakest link. To see how losing one faint satellite signal can beat a capable military, you have to look at the chain itself, and at the way modern force is composed.
Part Four · The kill chain
Every modern military runs the same kind of process: see the target, decide to hit it, hit it, check whether it worked. The American codification is linear: six discrete steps in a closed loop, easy to walk through. Other powers frame the same problem differently. The Soviets called theirs the Reconnaissance-Strike Complex. The Chinese have been formalizing a more systemic conception.
The American name is F2T2EA. First you find the target, when a satellite, a radar, or a scout notices it. Then you fix it, pinning it to coordinates a weapon can use, and track it if it moves. You target it (which weapon, what authority), then engage by firing, and finally assess whether it worked or whether you have to go again. All else being equal, the side that closes its own loop faster and breaks the other's gains a decisive operational advantage, though attrition, geography, and morale shape much of the rest of the contest.
Running the loop takes four standing capabilities. ISR (intelligence, surveillance, reconnaissance) does the finding and the fixing. Communications carry the coordinate from the sensor to the shooter. Weapons, the precision munitions, do the engaging. Logistics keep the force fed and every unit aware of where the others are, so the chain never fires on itself.
And what holds the four together is PNT (position, navigation, and timing): not a fifth pillar in line with the others, but the substrate the four stand on. Position turns "contact" into a grid square a weapon can fly to. The shared clock lets the sensor, the network, and the shooter act on the same tick, so a track passed from radar to datalink to launcher is still the same track when the trigger is pulled. The other four are standing capabilities. PNT is the layer underneath, the foundation the rest rest on.
ISR finds and fixes the target; communications passes the coordinate to the shooter; weapons engage; logistics keeps the force fed and aware of itself. These are the four standing capabilities that carry every step of the loop.
The fifth pillar runs through all of them. Position turns "something is there" into a coordinate. The shared clock lets the sensor, the network, and the shooter act on the same instant. PNT is not one of five; it is what holds the other four together.
Take PNT away and the links do not weaken — they stop locking together. The sensor still sees, the network still passes data, and the weapon still flies, but none of it is the same target.
The same timing layer stamps stock trades, synchronizes the power grid, runs container ports, lands aircraft. The kill chain is just the sharpest case of a civilization wired to a signal from twenty thousand kilometers up.
Pull PNT out and the links do not weaken. They delaminate; the chain comes apart in layers. The sensor still sees, but its read cannot be turned into a coordinate a weapon can fly to. The network still passes data, but the data no longer lines up. The weapon still flies, toward a point that has already drifted from meters to blocks. The exquisite platform cannot buy its way out of that vulnerability. Break the weakest link and the most expensive weapon in the inventory can become a tube aimed at open ground.
The Chinese version starts from a parallel lesson. Beginning after the 1991 Gulf War, sharpened by Kosovo in 1999 and Iraq in 2003, PLA strategists drew a foundational conclusion from watching the American kill chain operate. American dominance was not primarily about platforms. It was about the system that wired the platforms together, what PLA writing would come to call zuozhan tixi (作战体系), the operational system. The aircraft, the missile, the radar were nodes. What did the actual work of war was the system linking them.
What followed in PLA literature is not a single concept but a doctrinal stack. The outermost frame is xinxihua zhanzheng (信息化战争), informationized warfare, naming the broader condition: modern war is fought through, and against, information systems. Inside that, tixi duikang (体系对抗), or systems confrontation, names the operational mode: two operational systems contend, each trying to maintain its own coherence and degrade the other's. And inside that mode, tixi pojizhan (体系破击战), system-destruction warfare, names the specific theory of victory. You win by paralyzing the enemy's operational system, not by annihilating fielded forces. Earlier discussions of paralysis appear in the 2001 Science of Military Strategy; the explicit system-destruction vocabulary becomes visible across the 2000s and 2010s.
The unit of analysis is the enemy system. Targets are chosen at the system level, not by what is locally convenient to hit but by what would collapse the operational architecture. Sometimes that means destroying a high-value node: a command post, a comms relay, a logistics hub. Sometimes it means compromising the link between nodes: emissions, signals, satellite navigation, the trust between sensor and shooter. And for the most expensive nodes to physically reach, the link is often the cheaper attack: you don't have to shoot down the satellite if you can degrade the signal it sends. Counter-space, electronic warfare, cyber, deception, jamming, spoofing: in the Chinese conception these are not separate tricks. They are applications of one theory.
American doctrine has its own anti-system traditions: Boyd's OODA loop, network-centric warfare, a long lineage of attacking command-and-control. The U.S. has always thought about disrupting enemy decision cycles. But where these have generally been treated as one mode among many in American doctrine, system destruction sits at the center of the Chinese conception. That difference in centrality, more than the presence or absence of any single concept, reflects where each doctrine was written from. A power running the chain emphasizes running it. A late-arriving challenger watching the leader's strength emphasizes breaking it. The first treats integration as a capability to acquire. The second treats it as a vulnerability to find.
Iran's GPS shutoff during the June war. Israel's parallel PNT struggle. The J-10C and Erieye and Link-17 chain over Kashmir. Each is system destruction at work. The Chinese did not invent the techniques. Jamming and spoofing and cyber and deception are old, and so is space targeting.
Two things changed at once. The PLA wrote them into doctrine. The instinct is old: Chinese strategy has long sought to exhaust an adversary rather than break him in a single decisive battle. System-destruction warfare fits that instinct to a networked age. You win by denying the enemy the integration that binds his forces into one, and each year the exquisite parts are worth less without it.
The other change is the toolkit itself. China, together with other suppliers, has begun diffusing the components that let a motivated state practice system destruction without American patronage: sovereign navigation, integration-friendly fighters and missiles, datalink-ready radars. The doctrine and the toolkit have spread together.
And it is not only war. The same timing layer stamps stock trades, synchronizes the power grid, runs container ports, and lands aircraft. When it drops, ships appear to jump across continents and pilots reach for paper maps. The kill chain is only the sharpest case of a civilization that has wired itself, quietly, to a signal from twenty thousand kilometers up.
So how do you break that link without putting a weapon on the satellite? You don't need to. The signal is faint and the band is published; jamming and spoofing are ordinary background conditions of modern conflict, and the most PNT-dependent military on earth has been paying for both. There are two ways a satellite signal can be killed.
Part Five · How you break a signal
Electronic warfare is the contest inside the spectrum: the radar returns, the radio nets, the datalinks, the satellite communications (SATCOM), the satellite-navigation signals (GNSS) militaries use to see, talk, and steer. Instead of destroying his troops directly, you wreck the band his system breathes: blind his radar, cut his radios, corrupt his navigation. In a networked force, what happens in the spectrum can decide the exchange before the first weapon arrives. The slice of EW aimed at PNT has its own name, navigation warfare, and over the last decade it has gone from specialist concern to a near-constant background condition of modern conflict. Iran shut off GPS over its own airspace during the June war. Israel ran spoofing operations against Iranian drones. Russia has blanketed the Baltic with jamming since 2022. American precision munitions in Ukraine are now routinely defeated by Russian electronic warfare.
There are two ways to defeat a satellite signal at the receiver, and they are not the same. The first is to jam it: blast noise on the signal's frequency until the receiver can no longer pull the real signal out of the din. The second is to spoof it: broadcast a convincing counterfeit, so the receiver does not go blank but does something worse: it calmly computes a confident, precise, wrong position, one that passes every internal sanity check. There is a clean compression for the difference. Jamming silences the receiver; spoofing convinces it of the wrong thing.
The open civilian signal everyone's phone uses can resist neither attack. The L1 C/A broadcast arrives at the ground well below the receiver's own noise floor, recoverable only because the receiver knows exactly which pseudorandom pattern to listen for. A jammer the size of a cigarette pack, bought on the internet for fifty dollars, drowns it across a city block. And the L1 format is fully documented, so building a convincing fake is straightforward. That combination is why jamming and spoofing are now ordinary. The mechanics divide cleanly.
The harder of the two to detect is the spoof, because the receiver does not see a glitch. It sees a clean fix. And the takeover is not a sudden swap. It is a smooth handoff. A capable spoofer starts by broadcasting a signal that matches the real one almost exactly, then slowly walks the broadcast away from truth. The receiver follows. Its perceived position decouples from its actual position by inches, then by meters, then by kilometers, with no break in the displayed precision. Researchers call this the drag-off. There is no moment when the receiver flinches.
That asymmetry, the absence of any moment when the receiver flinches, is what makes spoofing the harder problem of the two. Jamming is loud. A receiver under jamming knows it has lost the signal: it can warn the operator, fall back on inertial guidance, refuse to act on stale data. Spoofing is silent. It hands the operator a wrong answer that the receiver itself cannot tell apart from the right one. Which leaves the question: how do you defend a signal against attacks like these?
Part Six · How you defend a signal
There is no single thing that makes a signal hard to jam or spoof. There is a set of techniques, layered, and each system combines them its own way. The foundation is one even the open civilian signal already has: spread spectrum. Every GNSS signal, civilian and military, is smeared thinly across a wide band, riding below the background noise. To jam it you cannot sit on one frequency; you have to flood the whole band, which costs far more power. Spread spectrum is the baseline. It is also why a civilian signal that has spread spectrum can still be jammed daily by a $50 device: the band is finite and the signal is faint enough that ordinary RF noise drowns it.
What militarizes the signal is encryption. Key the code with a secret. Only a receiver holding that key can acquire and track the signal, and nobody without it can forge a copy the receiver will accept. That one step does much of the anti-spoofing work.
A reported moment from the 2026 war suggests what that step looks like in the field. Israeli systems tried to feed false coordinates to Iranian drones on BeiDou's military signal, which public Chinese descriptions say is cryptographically signed at every broadcast. The receivers checked the signature, found that the fake was not signed with the right key, and rejected it. The spoof bounced off.
Beyond encryption, the two superpower constellations diverge. America's M-code, broadcast since the modernized GPS satellites began launching, but still waiting on user equipment and ground systems to deploy at scale, leans on power, and on aiming it. A focused spot beam can concentrate the hardened signal up to roughly a hundred times stronger over a chosen region for a chosen time. BeiDou's military signals reportedly add what M-code does not: frequency hopping, where the signal jumps across frequencies on a schedule a jammer cannot follow, and navigation message authentication, a cryptographic signature on every broadcast. Europe's Galileo runs an encrypted Public Regulated Service that resembles M-code most closely; Russia's GLONASS has its own military protections on an aging constellation. Neither yet competes for the role of the world's anti-jam tier; the contest the rest of this section is about is the GPS-BeiDou one. BeiDou's own bet on power runs the other way, toward breadth: a low-orbit layer planned for later this decade would raise the strength of the whole signal everywhere at once, since a satellite six hundred kilometers up is far closer, and far louder, than one at twenty thousand.
The difference in the two wars was cruder than any of this. In 2025 the weapons in the fight, Iran's among them, were still on the open civilian signal, which carries none of these protections. In 2026 Iran had switched, and had access to the hardened B3A tier. The jamming was as heavy as before, and this time it failed. Getting access to that tier is not something a country can do on its own: the keys, the receivers, the integration. Iran reportedly got them under the 25-year China–Iran partnership signed in 2021. The United States, by long policy, has never had to think about access this way. It builds its own.
The gap runs deeper than access. Even America's own National Space-Based PNT Advisory Board says so. In November 2022 it warned that GPS is "now substantially inferior" to BeiDou. The dimensions the quote applies to are fielded anti-jam protection and integrated functions, not the underlying signal design; the qualifier the language hides is "as fielded today." The next generation of GPS satellites carries the fix: Regional Military Protection, the hundred-times spot beam. But the program has slipped repeatedly, and the first satellite carrying it is not expected to launch before 2027. The US gap is fielding speed, not design ceiling. The next ten years will close it in the orbit GPS already flies. The architecture gap (orbit layers, messaging, integrated functions) is a 2030s question.
Spread spectrum, encryption, power, hopping, authentication — all of these are moves at the signal layer. In the Gulf, the signal layer was enough: one war lost on an open signal, the next fought on a keyed one. But the deeper difference between the two systems is not in the signal at all. It is in where the satellites orbit, and in what a constellation is allowed to become.
Continued in Part Two, The Changing Character of War: from the signal war to the system war.
