Security Challenges of the U.S. European Command

Key Chapter Title List

1. Euro-Atlantic Security Environment
2. Reconstitution of Russian Military Power
3. Russia's Strategic Partnerships
4. Threats in the Contiguous Region
5. U.S. European Command's Strategic Imperatives
6. U.S. European Command's Whole-of-Theater Posture
7. U.S. European Command's Operations, Activities, and Investments
8. Strengthening the NATO Alliance

Document Introduction

This report is based on the testimony submitted by General Christopher G. Cavoli, Commander of U.S. European Command (USEUCOM), to the U.S. Senate Armed Services Committee on April 3, 2025. The testimony comprehensively outlines the most severe security challenges facing the European theater since the end of the Cold War, with a core focus on the persistent threat posed by Russia and its impact on the transatlantic security architecture.

The report first systematically assesses the current strategic security environment in the Euro-Atlantic region, noting that Russia's war in Ukraine entering its fourth year signifies its continued willingness to use military force to achieve geopolitical objectives. Russia is actively conducting a destabilization campaign in Europe aimed at creating strategic dilemmas, including hybrid means such as cyberattacks, information warfare, and election interference. Its deepening strategic partnerships with the Chinese Communist Party, the Democratic People's Republic of Korea, and Iran further complicate the global security landscape, forming an "adversary bloc" aimed at undermining the advantages of the United States and its allies.

The core section of the report provides a detailed analysis of Russia's military reconstitution process. Despite suffering significant losses on the battlefield in Ukraine, the Russian military's size and equipment replenishment rates have exceeded expectations, with its defense industrial base producing tanks, armored vehicles, artillery, and missiles at an unprecedented pace. The report pays particular attention to the modernization of Russia's nuclear arsenal and its policy updates lowering the nuclear threshold, as well as its maintained full-spectrum capabilities in air, maritime, and cyberspace. The Russian military is learning from battlefield experience, making rapid adaptive adjustments, and integrating new capabilities such as drones and electronic warfare, intending to gain tactical and operational advantages for future battlefields.

To counter the aforementioned threats, the report outlines U.S. European Command's three strategic imperatives: defending the homeland forward, globally projecting U.S. combat power, and deterring Russian aggression against NATO. The report details USEUCOM's force deployments, capability development, and integration with allies across all European operational domains (land, sea, air, space, and cyberspace), including the deployment of F-35 squadrons, enhancement of maritime power, and coordination of cyber and space capabilities. Furthermore, the report highlights the operations, activities, and investments funded through the European Deterrence Initiative, which aim to enhance the readiness, interoperability, and deterrence credibility of U.S. forces and NATO allies.

Finally, the report emphasizes the historic modernization transformation underway within the NATO Alliance. This includes force structure adjustments based on regional defense plans, reorganization of command and control systems to better synchronize multi-domain operations, and the delegation of operational decision-making authority to military commanders. USEUCOM is accelerating NATO's modernization process through the ruthless prioritization of warfighting capabilities, urging European allies to assume greater responsibility in security affairs. The report concludes that in the face of Russia's persistent threat, sustained U.S. leadership, investment in advanced capabilities, and a sustainable transition to an ally-led European defense are crucial.