Is NATO Expansion the Real Cause of the Ukraine War?

A 2017 analysis by the National Security Archive at George Washington University, based on declassified documents, confirms that U.S. Secretary of State James Baker explicitly told Soviet leader Mikhail Gorbachev in ebruary 1990 that NATO would not move 'one inch eastward' if Germany reunified and remained in NATO. The documents show that this verbal assurance was given in the context of Cold War negotiations, though it was never codified in a formal treaty. This evidence is frequently cited by proponents of the view that NATO expansion violated an informal understanding with Moscow, providing a historical foundation for Russia's stated security grievances prior to the 2022 invasion.

The official communiqué from the 2008 NATO Bucharest Summit states: 'NATO welcomes the Euro-Atlantic aspirations of Ukraine and Georgia for membership in NATO. We agreed today that these countries will become members of NATO.' This declaration, made at the height of post-Cold War expansion, is a key piece of evidence for pro-expansion critics. They argue that this open-door policy, despite lacking a concrete Membership Action Plan for Ukraine at the time, was perceived by Moscow as a direct challenge to its sphere of influence, escalating tensions and creating the geopolitical conditions that culminated in the 2014 annexation of Crimea and the 2022 full-scale invasion.

In December 2021, two months before the invasion, the Russian oreign Ministry published draft treaties addressed to the U.S. and NATO demanding legally binding guarantees that NATO would halt its eastward expansion and withdraw its forces and infrastructure to pre-1997 positions. This document, widely covered by Reuters and other outlets, shows that Moscow framed its actions as a response to NATO's military build-up. Con-side analysts, however, note that these demands were maximalist and unrealistic, effectively constituting an ultimatum that a sovereign alliance could not accept, and that Putin's subsequent invasion demonstrates his true aim of regime change in Ukraine rather than a defensive posture.

In his 21 ebruary 2022 address, Russian President Vladimir Putin delivered a lengthy historical and ideological justification for the invasion, declaring that 'Ukraine is not just a neighboring country... it is an inalienable part of our own history, culture, and spiritual space.' He falsely claimed that modern Ukraine was created by Bolshevik Russia and that its government was a 'puppet regime' of the West. Con-side analysts argue that this speech, and his repeated assertions that Ukraine is a 'fictional' state, proves the war is driven by imperialist revanchism and a denial of Ukrainian sovereignty, not by NATO expansion. They contend that NATO membership was merely a pretext for a premeditated war of conquest, as evidenced by his refusal to acknowledge Ukraine's independent existence.