NextFin News - Europe is fighting a war that does not quite count as war, and the cost of that ambiguity is landing on its balance sheets. On August 4, a drone carrying hundreds of grams of military explosive was found on the tarmac at Leipzig/Halle Airport beside a Ukrainian cargo plane; its detonator failed. On the night of September 9-10, 2026, nineteen Russian drones crossed into Polish airspace, and NATO jets engaged them. Between those two points lies the central problem of 2026: Russia has built a campaign of sabotage, airspace violations and electronic warfare that stays deliberately below the threshold of armed attack, and Europe still has no response that is proportional, affordable and fast.
The Situation: A Campaign Below the War Threshold
The sequence of incidents is no longer dismissible as noise. At Leipzig/Halle, German investigators recovered three drones carrying explosives in and around the airport. The first, found beside a Ukrainian Antonov cargo aircraft on August 4, was packed with hundreds of grams of PETN military explosive and failed to detonate; a third device, found on a field west of the airport on August 14, carried 50 grams of RDX. Berlin formally attributed the operation to Russian state agencies on September 1. European Union foreign policy chief Kaja Kallas called it "state-sponsored terrorism" and warned that "attempts to intimidate Europe" would fail.
Germany's response was the most punitive of any major European power since the war began: it closed the Russian consulate in Bonn, terminated the lease for the Russian House cultural centre in Berlin, tightened border controls and moved against Russia's shadow fleet of tankers. The measures signal how far Europe is willing to go — and also how narrow the menu remains. Every tool Berlin deployed was diplomatic or economic. None of them could have intercepted a drone on a runway.
Then came the Poland incursion. Polish Prime Minister Donald Tusk said 19 Russian drones entered the country's airspace overnight, some flying deep enough to force the temporary closure of four airports, including Warsaw's Chopin hub. Polish F-16s and Dutch F-35s, supported by German Patriot batteries and an Italian AWACS surveillance aircraft, engaged the intruders; Tusk said three or four were shot down. One drone crashed into a house in the eastern village of Wyryki-Wola. Warsaw invoked Article 4 of the NATO treaty, triggering urgent alliance consultations. NATO Secretary-General Mark Rutte called the violation "absolutely reckless. It is absolutely dangerous." Moscow denied responsibility, saying the drones did not target Poland.
The economic and operational toll is diffuse but compounding. GPS jamming and spoofing around the Baltic and Kaliningrad have become persistent enough that Sweden's Maritime Administration warned sailors in June to navigate by radar or landmarks. Lithuania's communications regulator said in May that Russia had increased its GPS spoofing antennae from three to 36 since the start of 2025. On May 21, UK Defence Secretary John Healey's flight back from Estonia was jammed for the entire journey. A plane carrying European Commission President Ursula von der Leyen experienced signal disruption en route to Bulgaria in 2025, and a Spanish defence minister's aircraft encountered interference near Kaliningrad the same year.
Europe's response has been sanctions and summits. On September 2, Kallas said the EU was preparing to sanction an additional 1,600 individuals and entities linked to Russia's military sector, on top of the more than 3,000 already sanctioned since February 2022. European Commission President Ursula von der Leyen said authorities were looking at how "to cut deeper into Russia's war chest." But sanctions are slow, and they do not stop a drone at an airport.
The Threshold Problem: Why the Gray Zone Is a Strategy, Not an Accident
Russia's campaign is calibrated. Each incident is real, disruptive and attributable, yet individually small enough that invoking Article 5 or ordering a kinetic response looks disproportionate. The Leipzig drone failed to explode; the Polish incursion caused no casualties. That is the design. By keeping every single act below the level that would compel a unified military response, Moscow forces Europe into a defensive posture that is expensive, politically fractious and slow.
The data bear this out. The Center for Strategic and International Studies counted 34 serious sabotage and arson incidents attributed to Russian military intelligence in Europe in 2024, up from 12 in 2023 and just three in 2022. Western officials have tracked roughly 200 cases attributed to Russia since the invasion, spanning espionage, cyber operations, assassination plots and physical sabotage. This is not a series of isolated provocations; it is a sustained campaign that has grown faster than Europe's ability to answer it.
The mechanism is straightforward: impose costs on Europe without giving Europe a clean trigger to impose costs back. Sabotage at a logistics hub delays weapons shipments to Ukraine. A drone swarm over Poland forces NATO to burn expensive interceptors and reveals gaps in allied air defences. GPS jamming degrades civilian aviation without firing a shot. Each act is cheap; each response is expensive.
This is also, critically, a test of political cohesion. Article 4 consultations are non-binding; Article 5 requires consensus. A campaign of small, deniable acts exploits the gap between the two. If Moscow can force each incident into a separate diplomatic track — Berlin handles Leipzig, Warsaw handles the drones, Vilnius handles the jamming — it never has to face the alliance as a single adversary. Fragmentation is the objective, not a side effect.
The Cost Asymmetry: A $10,000 Drone Against a Multi-Billion Euro Shield
The economics of this conflict are brutal. Russian Shahed-style drones cost roughly $10,000 each. Intercepting them with fighter jets and missiles can multiply the cost tenfold. The proposed European Drone Wall, a layered network of sensors and interceptors, is estimated at €3 billion to €7 billion to implement — and that is only the down payment on a system that must cover thousands of kilometres of frontier.
Europe is spending. European NATO members are on track to allocate 2.3% of GDP to defence in 2026, the first full year the alliance has collectively exceeded the 2% target, and 2.5% excluding the United States. EU defence expenditure reached €418 billion in 2025 and is expected to hit €454 billion in 2026, an 8.6% annual increase and 75.3% above 2021 levels. Procurement and R&D now claim 36.2% of European NATO defence budgets, up from 24.8% in 2020 — a structural shift toward investment rather than personnel.
But spending is not the same as capability, and capability is not the same as a doctrine. NATO launched Operation Eastern Sentry in September 2025 to strengthen air defence along the eastern flank, and the EU is pushing a European Drone Defence Initiative under its Readiness Roadmap 2030. The Baltic states, Poland and Finland have announced a Baltic Drone Wall. Yet these programmes face disputes over cost, feasibility and strategic focus, and none of them solves the fundamental asymmetry: the attacker chooses the time, place and scale; the defender must be ready everywhere, all the time.
The fiscal trade-off is becoming visible. The International Monetary Fund projects the European defence ramp-up will reach 1% of GDP in 2026 and 1.3% by 2030. That is the first-order drag — and it is already reflected in the euro-area outlook. What is less understood is that the spending is concentrated in countries least able to absorb it. Poland now devotes more than 4% of GDP to defence, with equipment imports accounting for about 80% of its capital spending because domestic capacity cannot keep pace. Frontline states are rearming fastest while carrying the highest exposure to the very attacks they are buying protection against.
The Second-Order Problem: What the Market Has Not Priced
The conventional read is that higher European defence spending is a fiscal drag that will crowd out investment and weigh on growth. That is the first-order effect, and it is already reflected in the euro-area outlook. The second-order effect is different, and it is where the market is underpricing risk.
A persistent gray-zone campaign changes the risk premium on European assets in ways that budget totals do not capture. Aviation faces rerouting, wider separation standards, higher fuel reserves and rising insurance premiums in the Baltic region. The Lansing Institute has warned that repeated spoofing incidents may force airlines to carry additional fuel reserves, increase cockpit workload and accelerate costly avionics upgrades. Supply chains that depend on just-in-time air cargo — including the Ukraine support corridor through Leipzig — face recurring disruption risk. Energy infrastructure, already targeted by sabotage and drone strikes, carries a higher political-risk discount. These are not one-off shocks; they are a permanent tax on operating in Europe's eastern half.
Investors have already rewarded the obvious beneficiaries. European defence stocks surged more than 450% from the start of Russia's full-scale invasion through early 2026, compared with a roughly 40% gain for the broader MSCI Europe index. The STOXX Europe Aerospace & Defense Index traded at about 43 times expected 2026 earnings — more than double the valuation of the broader STOXX Europe 600. But that rally prices the spending, not the vulnerability. It assumes the money buys security. If the gray zone persists despite the spending, the premise weakens: higher budgets become a sign that the threat is structural, not that it is being solved.
The deeper implication is political. If Russia can keep incidents below the war threshold indefinitely, the deterrent value of NATO's conventional superiority erodes not through defeat but through irrelevance. That is the real second-order risk: not that Europe loses a battle, but that the battlefield keeps moving to a zone where Europe's strengths do not apply.
The Counter-Thesis: Europe Is Adapting Faster Than It Looks
The strongest case against this reading is that Europe has already crossed a Rubicon. European allies have warned at the United Nations that they will shoot down Russian jets or drones involved in any further violations of NATO airspace. NATO fighters have now fired at Russian drones over Poland — the first time alliance aircraft are known to have engaged enemy targets in allied airspace during the war. German Chancellor Friedrich Merz said those behind hybrid attacks "will pay," and German Foreign Minister Johann Wadephul warned that Russia would have to "live with the consequences of its actions," with a response "carefully prepared."
This view holds that the gray zone is self-limiting: push too far, and you trigger exactly the unity and rearmament you hoped to prevent. The September incursions have already hardened national positions and accelerated joint procurement of short-range air defence and counter-drone test centres. NATO allies announced in July that they would invest more than $40 billion in counter-drone capabilities over the next five years, alongside a commitment to train five times as many drone operators by the end of 2027.
The counter-argument is real, but it mistakes activity for resolution. Deploying jets to Poland is a response to a breach, not a prevention of the next one. Sanctions on 1,600 more entities will not deter an operation that costs $10,000 and is plausibly deniable. The falsifying signal is concrete: if, over the next six to twelve months, the frequency of attributed Russian hybrid incidents in Europe falls materially — say, back toward 2023 levels of roughly a dozen serious incidents per year — then the escalation-has-backfired thesis would be vindicated and Europe's response would be working as deterrence. If the tempo holds or rises, the gray zone has become the new normal, and Europe's current toolkit is insufficient.
Outlook: Three Scenarios
The near-term path is more of the same: incidents, summits, sanctions packages, and incremental defence deployments. The medium-term question is whether Europe can build a counter-drone architecture that changes the attacker's cost-benefit calculation. The long-term question is whether the West can establish a credible threshold for gray-zone warfare at all, or whether the post-1945 boundary between war and peace has quietly dissolved.
Base case: the campaign continues at current tempo, with Europe absorbing the cost through higher defence budgets and higher risk premiums. Defence equities outperform on order flow, while eastern European sovereigns and insurers carry a persistent geopolitical discount. Upside case: a coordinated European counter-drone wall, backed by shared intelligence and pre-authorised rules of engagement, raises the cost of attacks enough to suppress the tempo. That would require resolving the cost asymmetry — cheap interceptors, automated detection, and rules that let local commanders act without waiting for consensus. Downside case: a single incident with mass casualties — a drone hitting a passenger aircraft, a successful strike on critical energy infrastructure in winter — forces a kinetic response that Moscow did not intend and neither side can control.
What to watch: the EU's next sanctions package and whether it includes the proposed ban on former Russian military personnel; NATO's assessment of the Poland incursion; and the frequency of GPS jamming incidents reported by Baltic aviation and maritime authorities. The single most informative datapoint will be the incident tempo over the next two quarters: deterrence is working only if the attacks stop, not if the responses multiply.
"The fact that these drones, which posed a security threat, were shot down changes the political situation," Tusk told Polish lawmakers. "I have no reason to claim we're on the brink of war, but a line has been crossed, and it is incomparably more dangerous than before."
Europe's problem is not that Russia is winning a war. It is that Moscow has found a way to keep fighting without one — and every week that passes without a credible response teaches Russia that the strategy works.
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