NATO’s Hedgehog exercise exposed a brutal truth: 10 Ukrainians with drones wiped out two battalions in a day

A new Wall Street Journal report by Jillian Kay Melchior details for the first time what actually happened when Ukrainian drone operators faced off against NATO conventional forces during last May’s Hedgehog 2025 exercise in Estonia. The results were, by multiple accounts, a disaster for the alliance.

Here is what you need to know:

• The exercise: Hedgehog 2025 (Siil 2025 in Estonian) involved more than 16,000 troops from 12 NATO countries in a simulated Russian invasion scenario across Estonia.
• The result: A small team of roughly 10 Ukrainian drone operators, acting as the adversary force, mock-destroyed 17 armored vehicles and conducted 30 “strikes” on other targets in about half a day. Two NATO battalions were effectively eliminated.
• The source: The WSJ opinion piece, published February 12, 2026, draws on firsthand accounts from exercise participants and Estonian defense officials.

NATO troops moved like it was 2003, not 2025

The Hedgehog exercise simulated a Russian incursion across Estonia’s 294-kilometer border with Russia, triggering a full-scale NATO Article 5 response. The exercise ran from May 5 to 23, 2025, and featured heavy armor including British Challenger 2 tanks, Apache attack helicopters, and HIMARS rocket artillery. But the heaviest equipment wasn’t the decisive factor.

During one scenario, a battle group of several thousand troops, including a British brigade and an Estonian division, attempted to conduct an attack. Exercises like Hedgehog are designed to stress-test weaknesses, and this one delivered. As they advanced, they failed to account for how drones have made the modern battlefield completely transparent.

One participant told the WSJ that the NATO battle group was “just walking around, not using any kind of disguise, parking tents and armored vehicles.” The outcome? “It was all destroyed.”

During the exercise, Ukrainians operated their Delta battlefield management system for the first time on Estonian soil. Delta collects real-time intelligence from drones, satellites, sensors, and human sources, then uses AI to analyze the data, identify targets, and coordinate strikes across command and units. The kill chain runs fast: see it, share it, shoot it, all within minutes.

A team of 10 Ukrainians humiliated a conventional NATO force

A single team of roughly 10 Ukrainian operators, acting as the adversary, counterattacked NATO forces and mock-destroyed 17 armored vehicles while conducting 30 additional strikes on other targets. That took about half a day. The adversary forces were, according to Aivar Hanniotti, who coordinated unmanned aerial systems for the Estonian Defense League during the exercise and has since moved to the private sector, “able to eliminate two battalions in a day,” so that “in an exercise sense, basically, they were not able to fight anymore after that.”

The NATO side “didn’t even get our drone teams,” Hanniotti told the WSJ. Overall, the results for NATO forces were described as “horrible.”

Hanniotti led an adversary unit of about 100 personnel, including Estonians and Ukrainians, that deployed more than 30 drones against NATO troops in an area of less than 4 square miles. That’s only about half the drone saturation Ukrainian forces currently see at the front, though Lt. Col. Arbo Probal, head of the Estonian Defence Forces’ unmanned systems program, noted that exercise umpires sometimes offset the discrepancy by recording drone strikes as twice as damaging.

Even with less reconnaissance than real combat conditions, Hanniotti said, “there was no possibility to hide. We quite easily found cars and mechanized units, and we were able to take them out quite fast with strike drones.”

Estonia already knew old-style maneuver warfare was dead

The WSJ report confirms what Estonian public broadcasting (ERR News) reported during the exercise itself. Reserve Major Sten Reimann, who organized Delta’s participation, said the key lesson was clear: “The old maneuver tactics, moving in large daytime convoys, just aren’t viable on the battlefield anymore.”

Hanniotti, speaking to ERR at the time, described a battlefield buzzing with drones constantly. “There are so many drones flying at our exercise that I’ve never seen anything like it. Battlefield information from the drones was relayed within minutes.”

We’ve been covering this shift for months: Ukraine’s role has flipped from NATO student to NATO teacher.

Danish Prime Minister Mette Frederiksen said it outright at last year’s Copenhagen summit: “The only expert right now in the world when it comes to anti-drone capacities is Ukraine.” The Hedgehog results prove she was right.

The numbers gap is staggering

Security expert and reserve officer Ilmar Raag, who was embedded with one of the Ukrainian drone groups at Hedgehog, published a sobering analysis afterward. Ukrainian drone pilots calculated that Estonia alone would need approximately 200,000 drones per month during wartime, based on current Ukrainian consumption rates. Ukraine itself scaled its drone production from 2.2 million units in 2024 to 4.5 million in 2025. NATO allies are nowhere close to matching that industrial capacity.

The exercise also exposed a training gap. During one engagement, a single Estonian FPV drone eventually reached an enemy tank. The Ukrainians watching said that by that point, 8 to 10 drones should have already been inbound, since one is rarely enough. That’s not a criticism of individual operators. It’s a systemic problem requiring more funding, more pilots, and a fundamentally different approach to force structure.

Worth noting: U.S. troops were absent from Hedgehog 2025. European defense officials declined to speculate on the missing American presence. That absence is telling in its own right.

DroneXL’s Take

This WSJ report is the most damning public account yet of NATO’s drone warfare readiness gap. We’ve covered Ukraine’s evolution from Aerorozvidka stopping Russian convoys with volunteer-built drones in 2022 to deploying AI-powered swarms and autonomy modules that quadruple hit rates. And we’ve watched NATO allies slowly, painfully try to catch up, from Norway’s first operational drone swarm to Estonia’s scrappy Defense League innovations.

But here’s the hard fact: 10 people with drones and a laptop running Delta eliminated more combat power in half a day than most NATO battalions could generate in a week of conventional operations. That’s not a technology problem. It’s a doctrine problem. NATO still trains, moves, and fights as if the sky is empty. Ukraine proved three years ago that it isn’t.

The absence of U.S. forces from this exercise should alarm everyone. If European NATO members are struggling to adapt, the alliance’s largest military contributor wasn’t even in the room to learn the lesson.

Expect this report to accelerate European drone procurement over the next six months, particularly in the Baltic states. Estonia’s “Angry Hedgehog” loitering munition program and its new Kullisilm dedicated drone unit will likely see increased funding. But production timelines and operator training remain the bottleneck. You can buy drones fast. You can’t train an army to think differently overnight.

Editorial Note: AI tools were used to assist with research and archive retrieval for this article. All reporting, analysis, and editorial perspectives are by Haye Kesteloo.