[UPDATED: Sept. 10, 3:52 pm , Kyiv time. Updated the number of Russian drones in Poland]

On Wednesday, Sept. 10, Poland is reportedly invoking NATO’s Article 4 after multiple Russian drones flew into Poland.

While there have been minor incursions in the past, this was the first of its kind since Russia’s 2022 full-scale invasion of Ukraine, with an unprecedented 19 drones entering Polish airspace during a Russian strike on Ukraine and forcing the closure of four Polish airports.

Some of the drones also entered from Belarus – host of the ongoing Zapad (“West”) war games with Russia – just days after Poland closed its border with Belarus in response.

But what is Article 4? Is NATO readying for war? How many times has it been invoked in the past?

What is NATO’s Article 4?

Article 4 can be interpreted as emergency consultations among alliance members, which may or may not lead to military actions.

In NATO’s words, it is invoked when a member’s integrity and security are threatened.

“The 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,” the article states.

The consultations will be carried out via the North Atlantic Council, the alliance’s principal political decision-making body. All members of the council are required to address the issue brought by a member state.

A Center for European Policy Analysis (CEPA) article said the clause was originally intended to cover NATO members’ colonial interests during its inception, as the vague definition allows member states to rally support for overseas interests – though it has never been used for such cases in reality.

Article 4 does not automatically lead to military action – though it has preceded such steps in the past – unlike Article 5, which functions as NATO’s war clause, obliging a collective response if a member is attacked.

Because invoking Article 5 requires unanimous approval, it is unlikely to be triggered in the current political climate – with Hungary’s ties to the Kremlin and the Trump administration’s floating its isolationist notions of withdrawing from Europe, among other factors.

How many times has Article 4 been invoked?

The article has been invoked seven times since NATO’s founding – all of them after 2000 and tied to crises in either the Middle East or Eastern Europe.

Below is a condensed list of occurrences:

• 10, 2003 – Turkey: Requested consultations over threats from the Iraq War; NATO launched Operation Display Deterrence (February-May 2003), in which NATO assets were deployed to Turkey, with Airborne Warning and Control System (AWACS) aircraft flying 100 missions with a total of 950 flying hours.
• June 22, 2012 – Turkey: Called for consultations after Syria shot down a Turkish RF-4 reconnaissance jet over the Mediterranean, which resulted in a condemnation statement.
• 3, 2012 – Turkey: Invoked Article 4 (after deciding to de-escalate and not to invoke Article 5) after Syrian shelling killed five civilians; later requested Patriot missiles, which NATO deployed as part of Operation Active Fence.
• March 3, 2014 – Poland: Requested consultations over Russia’s actions in Ukraine (the occupation of Crimea).
• July 26, 2015 – Turkey: Requested consultations after terrorist attacks and to brief allies on its response, which led to another condemnation statement.
• Feb. 28, 2020 – Turkey: Invoked Article 4 after Turkish soldiers were killed in Russian-backed Syrian airstrikes in Idlib, resulting in a condemnation statement in solidarity with Turkey.
• Feb. 24, 2022 – Bulgaria, Czechia, Estonia, Latvia, Lithuania, Poland, Romania, Slovakia: Jointly requested consultations after Russia’s full-scale invasion of Ukraine, which led to more defense postures on NATO’s eastern flank. The invasion itself accelerated Finland and Sweden’s accession into the alliance.