Constanța blast exposes NATO drone blind spot

At 6am on June 5, Romanian forces spotted a Ukrainian naval drone inside the civilian port of Constanța, NATO's largest Black Sea logistics hub. Then came the silence. At 10am, Ukraine told Romania it had lost control of four drones after Russian electronic warfare jamming. At 10.28am, the drone blew itself up at berth 78, about 500 metres from an oil terminal (Agerpres, Straits Times).

Nobody was killed. The more serious fact was the four-hour gap between detection and warning. Romania had found an armed drone in a civilian port, but there was no agreed protocol for what came next.

It was not an isolated incident. On May 7, fishermen found a Ukrainian drone carrying explosives in a sea cave off Lefkada in Greece, its engine still running (skai.gr). In both cases, Ukraine blamed Russian electronic warfare for the loss of control (Maritime Executive).

Built for Ships, Blind to Drones

Romania's coastal surveillance system, SCOMAR, was built to track vessels larger than six metres. Ukrainian Sea Baby drones are roughly five metres long. The Interior Ministry acknowledged that small platforms with low radar signatures "were not among the objectives for which the system was originally designed." Constanța's recently installed counter-drone system covers the air, not the water surface (HotNews).

The institutional map is no cleaner. Defence Minister Radu Miruță said the military does not guard civilian ports. The coastguard watches traffic. The port authority manages the site. Four institutions share responsibility for Constanța, but none had a plan for an armed drone entering the harbour.

Romania also has a political blockage in the way of a technical fix. Its multibillion-euro SAFE defence procurement programme, designed partly to close low-altitude and surface surveillance gaps, has been stalled by a constitutional court challenge from members of the same governing coalition that approved it. Until that is resolved, NATO's largest Black Sea port is relying on sensors designed for cargo ships.

Bulgaria, further down the same coastline, activated radar and helicopter patrols within hours. It faces the same basic problem: surveillance systems calibrated for conventional vessels, not five-metre drones with tiny radar signatures (armymedia.bg).

A Security Hub That Exists Only on Paper

The EU's proposed answer is a Black Sea Maritime Security Hub. For now, that means very little. It has no legal basis, no budget and no host city. It comes from a 2025 Joint Communication, which is a policy paper rather than a binding instrument (EEAS).

Romanian MEP Victor Negrescu has called for the hub to be accelerated after the Constanța explosion. But acceleration is a thin word when the starting point is still a concept document.

A leaked EU Council document from May 2026 showed that each country still treats drone security as its own national problem. Member states are operating "in silos", with no shared system for detection or response (Euronews). The EU's counter-drone action plan, adopted in February 2026, promises a maritime awareness "pilot action", with full deployment not expected before 2030 (Counter-UAS Action Plan).

Even that plan is aimed mainly at threats from the air. Surface naval drones barely appear in it.

A Treaty Designed for a Different Kind of Ship

The legal framework is older than the weapon. The 1936 Montreux Convention governs naval passage through the Turkish Straits between the Black Sea and the Mediterranean. It sorts vessels into merchant or military categories. Naval drones sit awkwardly outside both.

They have no crew, no commissioned officer, and Ukraine has not registered them as warships (Opinio Juris). Turkey has neutralised at least 11 stray drones in its waters, but has avoided saying what they are under the convention (Daily Sabah).

That silence suits Ankara. If Turkey opens the legal question, it may have to restrict Ukrainian drones or formally recognise their right of passage.

The Constanța drone hit a breakwater, not a tanker. Romania has since asked Ukraine to notify it whenever control of a weapon is lost. That bilateral request is, for the moment, Europe's working system: a country asking the drone operator to phone ahead when things go wrong, while ports remain exposed and the legal framework still does not admit that these weapons exist.