Despite what will transpire in Russian President Vladimir Putin’s invasion of Ukraine, the largest war in Europe since World War II has permanently impacted the region’s defense climate. As a result, we can expect a significant change in the North Atlantic Treaty Organization’s (NATO) approach to deterrence.

In a piece published by the Brookings Institution, Director of Research in Foreign Policy Michael E. O’Hanlon argued for the abandonment of NATO’s tripwire approach and to replace it with a more permanent defensive posture in eastern Europe.

“Russian President Vladimir Putin must know of NATO’s unambiguous commitment to defend alliance territory and feel no doubt that the United States and its allies would do whatever it took to prevail in a war that he might initiate against one or more of the alliance’s members,” O’Hanlon wrote.

In response to Russia’s illegal annexation of Crimea in 2014, the members of the Alliance agreed to bolster NATO’s Enhanced Forward Presence in the east. In 2017, the first four multinational battalion-size battle groups were established in Estonia, Latvia, Lithuania, and Poland as part of the Alliance’s enhanced forward presence.

These combat-ready detachments are led by the United States, Canada, Germany, and the United Kingdom. The battalions represent the strength of the Alliance and its commitment to the treaty’s Article No. 5 Collective Defense, which stipulates that an attack against one ally is considered an attack against all allies.

U.S. Army Paratroopers assigned to the 82nd Airborne Division walk to their aircraft at Pope Army Airfield, N.C. Feb. 14, 2022. The 82nd Airborne Division is being deployed to reassure our NATO allies, deter any potential aggression against NATO’s eastern flank, train with host-nation forces, and contribute to a wide range of contingencies. (U.S. Army photo Sgt. Hunter Garcia).
U.S. Army Paratroopers assigned to the 82nd Airborne Division walk to their aircraft at Pope Army Airfield, N.C. February 14, 2022. (U.S. Army photo Sgt. Hunter Garcia).

Following Moscow’s invasion of Kyiv on February 24, NATO members have agreed to expand its Forward Presence by establishing four battle groups strategically placed in Hungary, Bulgaria, Slovakia, and Romania. This extends the presence of NATO forces along its eastern flank from the Baltic Sea in the north to the Black Sea in the south.

“I expect leaders will agree to strengthen NATO’s posture in all domains, with major increases of forces in the eastern part of the Alliance, on land, in the air, and at sea. The first step is the deployment of four new NATO battle groups in Bulgaria, Hungary, Romania, and Slovakia,” NATO Secretary-General Jens Stoltenberg said last March during the NATO meeting in Brussels.

“Between now and the NATO summit in June, we will develop plans for additional forces and capabilities to strengthen NATO’s defenses,” President Biden said. “We will adopt an updated Strategic Concept to ensure NATO is ready to meet any challenge in the new and more dangerous security environment.”