A European Article 4 would strengthen defence against hybrid threats

European Commission President Ursula von der Leyen has proposed creating a European Union security protocol modelled on NATO’s Article 4 to coordinate responses to hybrid attacks. The debate arrives alongside wider warnings from intelligence leaders. In his annual threat address, Sir Ken McCallum, the head of the UK’s MI5, warned that artificial intelligence has the potential to "change the stakes" on biological weapons and emerging technical threats.

To be sure, national capitals have raised valid concerns about the proposal, citing risks of duplicating NATO structures and exposing political divisions within the Union. Intelligence remains a core national responsibility, and member states are understandably cautious about creating redundant political bodies.

However, hybrid aggression—from cyber sabotage to AI-enabled threats—is explicitly designed to exploit gaps between national borders. Fragmented responses leave individual European states vulnerable to targeted disruption. A dedicated EU protocol would not supplant NATO’s collective defence obligations. Instead, it can give European governments a formal channel to consult rapidly, pool intelligence, and coordinate civil resilience when non-military networks are under attack.

Europe can enhance its collective security by establishing clear protocols for joint threat assessment. Moving past hesitation on coordinated defence will ensure the bloc is prepared when shared systems come under pressure.

Drafted with AI, edited by the editor.