The November 2025 National Security Strategy of the United States of America (NSS 2025) marks a decisive shift in Washington’s strategic outlook. Framed explicitly around restoring American strength at home, the document articulates a worldview that prioritises sovereignty, economic nationalism, and selective global engagement over liberal internationalism. While the Strategy does not signal isolationism, it redefines U.S. leadership as conditional, transactional (explicitly), and increasingly dependent on allied burden-sharing.
This Issue Brief analyses the NSS 2025 from two interlinked perspectives: first, the United States’ strategic priorities, assumptions, and expectations of allies; and second, how this strategy is likely to be interpreted in Europe, where it both reinforces and strains transatlantic security arrangements?
