European nations are significantly increasing their defense spending and bolstering capabilities, aligning with a strategic shift towards what is being termed "NATO 3.0." This evolution of the alliance emphasizes European allies taking greater responsibility for the conventional defense of the continent.
This new focus, championed by US Under Secretary of Defense for Policy Elbridge Colby and adopted by NATO Secretary General Mark Rutte, seeks to shift the security burden more equitably. The concept builds upon historical phases of NATO, with "NATO 1.0" characterized by a clear-eyed deterrence and defense approach before the Soviet Union's collapse, and "NATO 2.0" marked by a shift in focus and European disarmament, during which the US provided the predominant military power for European defense.
US Secretary of Defense Pete Hegseth has initiated a review of US bases and capabilities in Europe as part of the NATO 3.0 framework. European allies have responded to Washington's calls by increasing collective defense spending by nearly 20% in 2025. Already, five European nations are projected to meet the 3.5% of GDP defense spending target almost a decade ahead of schedule. Germany, for instance, is deploying a forward-stationed armored brigade in Lithuania to reinforce deterrence on NATO's eastern flank.
This increased investment aims to produce tangible "outputs and capabilities," including ready forces, available munitions, resilient logistics, and integrated command structures. These developments are crucial for NATO's deterrence posture, especially given the resurgent threat from Russia, as evidenced by its actions in Georgia and Ukraine.
Historically, NATO invoked Article 5 following the September 11, 2001 attacks, treating the assaults on the United States as an attack on all member nations. European and Canadian allies deployed tens of thousands of troops to Afghanistan, fighting alongside American forces for two decades, with over 1,000 allied service members making the ultimate sacrifice.
However, questions persist regarding the US commitment to the alliance, particularly in light of President Trump's past statements and actions. The reduction of US combat power in Europe, such as the end of the US Army's rotational Infantry Brigade Combat Team deployment to Romania, raises concerns about a potential interim deterrence gap. The success of NATO 3.0 hinges on whether reductions in the US military posture in Europe are carefully managed and on how Russia perceives the commitment of the United States to collective security.