The NATO air defence playbook that Western militaries have relied on for decades is no longer fit for purpose, Air Chief Marshal Sir John Stringer, NATO’s Deputy Supreme Allied Commander Europe, told Business Insider in a wide-ranging interview published on 21 June 2026.
Stringer’s warning comes as wars in Ukraine and the Middle East demonstrate that adversaries can now flood the skies with cheap, expendable weapons faster than expensive interceptors can be replenished. ‘The days of thinking that you can sit back and be reactive and engage every threat that comes at you using traditional means like fast jets and some surface-to-air missiles,’ he said, ‘those days are over.’
The Cost Curve NATO Cannot Ignore
The core problem is economic. Iran’s Shahed-style one-way attack drones cost an estimated $20,000 to $50,000 each, ABC News, citing an expert, puts the Shahed-136 specifically at around $35,000 per unit. Patriot Advanced Capability-3 interceptors, by contrast, cost roughly $3.7 million each. Stringer called using a PAC-3 against a Shahed-style drone ‘the most obvious example of getting that wrong.’ ‘That’s unsustainable,’ he said.
The stockpile strain is already prompting industrial responses. The Pentagon signed a $4.7 billion contract with Lockheed Martin on 10 April 2026 to expand PAC-3 interceptor production from 600 to 2,000 units annually over a seven-year period, alongside parallel expansions in THAAD and other missile-defence programmes. Yet Stringer’s point is that volume alone will not solve the mismatch if the price gap between attacker and defender remains so wide.
Western forces need ‘to play catch-up’ and respond ‘on the right part of what we call the cost curve,’ he said. That means investing in cheaper interceptors, counter-drone technologies, and electronic warfare rather than relying solely on premium systems.
Who Is Telling NATO to Rewrite the NATO Air Defence Playbook
Stringer is a former RAF fighter pilot who flew in the Balkans and Iraq before rising through the service’s senior ranks, according to The Telegraph. His appointment as DSACEUR was announced on 22 January 2026, making him the first RAF officer to hold the post since 1984 and only the third in the alliance’s history. He took up the role in March 2026, having previously served as Deputy Commander of NATO’s Allied Air Command at Ramstein, Germany, from August 2022.
That operational background in contested airspace informs his view that the threat has widened well beyond what NATO’s traditional posture was built to handle. ‘The threat is now everything from cheap air systems, uncrewed air systems, drones at one end of the spectrum to air-launched ballistic missiles’ and hypersonic weapons at the other, he said.
Offence, Industry and the Limits of Pure Defence
Stringer argued that passive defence, even at scale, is insufficient. Air power doctrine stretching back roughly a century holds that ‘your defence needs a good offense,’ he said, and that principle still applies. ‘You’ll hear people talk about going against the archer, not just the arrow. That’s true up to a point,’ he said, ‘but I actually want to go after the places where the arrows are made.’
He pointed to Ukraine as a model for industrial agility, noting the speed at which Kyiv has developed and fielded new weaponry by drawing in companies with no traditional defence background. ‘How many of them were even in existence five years ago, let alone how many of them spawned out the kind of traditional defense background or defense industrial background?’ he said of the innovative drone firms now supplying Ukrainian forces.
Ukraine has also shown practical ways to close the cost gap, developing cheap interceptor drones to knock down incoming threats rather than burning through expensive missile stocks. Stringer said the West needs cheaper sensors of the kind Ukraine already deploys alongside the powerful legacy systems NATO fields.
Even the command architecture used to coordinate air warfare needs to adapt. Large, centralised command centres that direct patrols, process sensor feeds, and allocate defences will need to become more dispersed so they are harder to target, Stringer said, even though dispersal makes air operations more complex.
On air superiority itself, Stringer acknowledged that full, persistent control of the sky may no longer be achievable in a large-scale conflict. General David Allvin, when he served as Chief of Staff of the US Air Force, had already warned that Ukraine’s war showed the United States it might not be able to enjoy ‘ubiquitous air supremacy for days and weeks on end.’ Stringer agreed the nature of the challenge has changed, but held firm on the objective: ‘You still need to secure air superiority. The ways of doing it may change, but it fundamentally provides a foundation on which the entire joint force operates.’
Whether NATO’s defence industries can scale fast enough to match the volume of cheap threats being produced is the question the alliance will need to answer before the next major conflict, not during it.