{"id":26215,"date":"2025-09-25T16:00:40","date_gmt":"2025-09-25T14:00:40","guid":{"rendered":"https:\/\/voelkerrechtsblog.org\/?p=26215"},"modified":"2025-09-29T17:53:00","modified_gmt":"2025-09-29T15:53:00","slug":"testing-natos-resolve","status":"publish","type":"post","link":"https:\/\/voelkerrechtsblog.org\/de\/testing-natos-resolve\/","title":{"rendered":"Testing NATO\u2019s Resolve"},"content":{"rendered":"

In the early morning hours of 10 September, Russia launched at least 19 Shahed-like Gerlan drones as well as smaller Gerbera decoy drones<\/a> from both its own territory and Belarus directly toward Polish sovereign airspace. Up to four drones, each about 4.5 meters long, posing \u201ca direct threat<\/a>\u201d were shot down by expensive fight jets<\/a>. In one attempt to shoot down the Russian drone, a missile struck a civilian building<\/a> in the Lublin area near the Ukrainian border. Contrary to Russian propaganda<\/a>, these were not false-flag operations or Ukrainian provocations. Said incursion \u2013 whether intentionally or unintentionally<\/a> \u2013 was a clear violation of Polish sovereignty and the prohibition on the use of force as well as a deliberate provocation to test NATO\u2019s resolve.<\/p>\n

This blog post argues that sound countermeasures grounded in international law are urgently needed to defend the international law-based order\u2014or what remains of it. Without such measures, Russian \u201cgrey zone\u201d operations, designed to push the boundaries of what is legally and legitimately permissible in the use of force, are likely to succeed over time. An early illustration of this dynamic occurred on 19 September, when three Russian MiG-31 fighter jets<\/a> violated Estonian airspace for approximately 12 minutes. Despite limited responses to the Russian drone incursion into Poland, such as Operation Eastern Sentry<\/a>, no significant countermeasures were taken, effectively incentivizing Russia to continue its breaches of international law.<\/p>\n

NATO\u2019s First Time Ever Engagement in Allied Airspace<\/strong><\/p>\n

As a consequence of the Russian attacks, Poland\u2019s operational command announced alert level and requested support from NATO\u2019s Allied Air Command (AIRCOM) as well as the Dutch F-35 air force. In addition, German Patriots air defense systems were placed on alert, while Italian airbone early warning aircrafts (AWACS) and an aerial refueler from NATO\u2019s Multinational Multi-Role Tanker Transport (MRTT) aircraft fleet were deployed that morning. Although Poland had faced several smaller drone incidents before, this was the first time ever<\/a>, NATO aircrafts engaged in potential threats in Allied airspace.<\/p>\n

Henceforth, Poland requested a UN Security Council emergency session<\/a> that took place on 12 September. In its letter, Poland calls the Russian provocation an \u201cattack\u201d with \u201cno doubt that this was not accidental\u201d. Polish Foreign Minister Sikorski<\/a> intended to \u201cdraw the world\u2019s attention to this unprecedented Russian drone attack on a member of the UN, EU and Nato\u201d. Although 40 countries (with mostly EU and NATO countries) signed a statement<\/a> rejecting Russia\u2019s violation of the UN Charter, no immediate sanctions followed.<\/p>\n

The provocation took place only two days before the military exercise \u201cZapad 2025<\/a>\u201d in Belarus, which literally means \u201cWest\u201d and was aimed at training Russian and Belarusian military movements in that direction. In fact, Belarusian territory and the Russian exclave Kaliningrad are only separated by less than 100km, the so-called Suwa\u0142ki gap that crosses Polish and Lithuanian territory. Hence, Russia appears to be testing NATO\u2019s responses through \u201cgrey zone techniques<\/a>\u201d. Instead of an overt military build-up at the Polish border, a plausible aim could be the division of the West to slowly expand its power and territory not only over Ukraine but potentially also over Poland and the Baltic states. Military experts such as Prof. Carlo Masala<\/a> have outlined this as a plausible scenario, though it has not (yet) fully materialized.<\/p>\n

Countering the \u201cGrey Zone Narrative\u201d<\/strong><\/p>\n

\u201cGrey zone techniques\u201d are also part of Chinese warfare in the Indo-Pacific<\/a> around Taiwan. The term suggests legal ambiguity, indicating that actions are not quite legal, nor quite il<\/em>legal. Thereby, revisionist powers like China and Russia are attempting to push the boundaries towards what appears to be legal and legitimate. According to the Lotus-principle<\/a>, \u201cwhatever is not explicitly prohibited is permitted\u201d. Yet international law is clear in that regard: Article 2(4) UN-Charter does prohibit the threat as well as the use of force and protects sovereign borders. Military drones can be seen as military aircraft of a special type, according to Article 3 of the Chicago Convention on International Civil Aviation<\/a>. The drones deployed on 10 September were Russian Gerlan models (similar to the Iranian Shahed) as well as smaller Gerbera decoy drones occasionally used as \u201cflying bombs<\/a>\u201d equipped with small warheads. Therefore, one must distinguish between reconnaissance and military drones. The incursion of non-military equipped drones without warheads constitutes only a violation of sovereignty according to Article 2(1) UN-Charter. However, the mere presence of military drones on foreign territory constitutes at least a threat of military force<\/a> and is therefore a violation of Article 2(4) UN-Charter. Not every violation of the use of force constitutes an \u201carmed attack<\/a>\u201d that allows for self-defense measures to take place. However, also less grave forms<\/a> can be countered according to Articles 31\u201339 and 49\u201354 ASR<\/a>.<\/p>\n

Article 4 NATO Treaty Countermeasures<\/strong><\/p>\n

In this sense, later that morning, the North Atlantic Council convened to discuss the ongoing situation after Poland\u2019s request for consultations under Article 4 NATO Treaty: \u201cThe Parties will consult together whenever, in the opinion of any of them, the territorial integrity, political independence or security of any of the Parties is threatened.\u201d<\/p>\n

Unlike Article 5 NATO treaty, Article 4 does not presuppose an armed attack and is therefore the first and foremost step to discuss coordinated legal countermeasures against the use of force violation.<\/p>\n

NATO Secretary General Rutte stated that the violation of Polish airspace was \u201cnot an isolated incident<\/a>\u201d. Concrete countermeasures were not announced by NATO. Later that day, Poland established a no-fly zone<\/a> close to its border with Ukraine and Germany announced<\/a> to extend its Air Policing activities to Polish airspace. Two days later<\/a>, France, Germany and Denmark announced that they will contribute fighter jets and other military assets, resulting in Operation Eastern Sentry<\/a>. However, none of these measures has had a significant impact on Russia and is arguably ineffective in preventing future provocations, as demonstrated just ten days later when Russia again violated NATO airspace, this time in Estonia, triggering again NATO\u2019s Article 4<\/a>.<\/p>\n

Since Russia\u2019s ongoing war of aggression already triggers not only Ukraine\u2019s right to self-defense under Article 51 of the UN Charter but also the collective right to self-defense<\/a>, its violation of the prohibition on the use of force against Poland (and Estonia) does not alter the already existing legal opportunities for EU and NATO members to act collectively since 2022. What the events of 10 September and following do, however, is raise the political urgency to react collectively now.<\/p>\n

Here are a couple of legal countermeasures that could be taken to support Ukraine\u2019s collective right to self-defense and react to the use of force violation against Poland as well as Estonia:<\/p>\n