The Russo-Ukrainian War and Its Impact on NATO

Abstract

This study analyzes the extent to which the Russo-Ukrainian War has influenced the structure of the North Atlantic Treaty Organization (NATO) and the policies of its member states amid the protracted nature of the conflict since February 2022 and the accompanying strategic shifts, most notably the positions of successive U.S. administrations. The research problem is framed around the central question: To what extent has the Russo-Ukrainian War reshaped the security and defense policies of NATO member states, and how has the shift in U.S. administration—particularly the return of Donald Trump to the presidency— affected the alliance’s future and its continued support for Ukraine?

The study adopts two complementary approaches: the descriptive–analytical method to collect and organize data in a way that serves the research objectives, and the institutional approach to observe and analyze NATO’s dynamics as an international organization with a distinctive nature that can both influence and be influenced by the war. The paper briefly addresses the background, causes, and developments of the conflict, then focuses on its implications for NATO members and the alliance’s future, with particular attention to how U.S. policy—from the Biden administration to the Trump administration—has interacted with the crisis.

The findings reveal that Western support, led by NATO states, enabled Ukraine to withstand Russia during the first three years of the war. However, the change of U.S. administration in January 2025 signaled emerging divergences between Washington and its European allies, indicating a potential decline in American support for Ukraine and casting uncertainty over the alliance’s cohesion and its capacity to address new security challenges.