The US National Security Strategy and the Imperative of European Autonomy

The December 2025 release of the US National Security Strategy (NSS) has shifted the debate on European Strategic Autonomy (ESA) from a long-term aspiration to an immediate strategic concern. Through a quantitative assessment of industrial dependency, structural inefficiency, and critical capability deficits, this article evaluates the European Union’s ability to respond to Washington’s new burden-shifting approach.

Published on 4 December 2025, the US NSS clearly redefined the alliance, making its security support dependent on specific European actions. The document emphasised that European partners must assume “significantly greater responsibility” for regional defence (US National Security Strategy 2025, Chapter 4). This reflects Washington’s intention to reallocate strategic focus, particularly towards the Indo-Pacific. Additionally, the NSS articulated a subtle critique of “transnational” European governance structures, implicitly questioning the effectiveness of EU-level coordination (US NSS 2025, Appendix B). The implication is straightforward: Washington is signalling that continued support depends on Europe’s capacity to develop autonomous regional deterrence. Nevertheless, several structural issues complicate such a response. In fact, Europe’s recent surge in defence spending is being undermined by two main constraints: a deepening dependence on US industry and persistent inefficiencies rooted in fragmented procurement systems.

Industrial Dependency and the Lock-in Effect

Despite political declarations on autonomy, the post-2022 increase in European defence spending has produced a significant expansion in purchases from the US defence industrial base. The total value of notified Foreign Military Sales (FMS) from the United States to European allies rose from an annual average of roughly USD 11 billion between 2017 and 2021 to USD 68 billion in 2024 (Mejino-López and Wolff 2025). These figures are confirmed in annual reports from the US Defense Security Cooperation Agency (DSCA 2024).

This nearly fivefold increase is more than a quantitative trend. It represents a long-term technological and operational lock-in. Platforms such as the F-35 or PATRIOT air defence systems entail extended reliance on US training pipelines, software, spare parts, and maintenance. These embedded dependencies grant Washington significant strategic leverage over European capability generation (Mejino-López & Wolff 2025). The US demand for Europe to take on more defence costs, therefore, highlights a fundamental difference in power that Europe itself has worsened by consistently buying foreign military equipment.

Structural Inefficiency and the ‘Cost of Non-Europe’

The second constraint is internal. Defence procurement fragmentation across 27 national systems prevents economies of scale and generates large efficiency losses. The European Parliamentary Research Service (EPRS) estimates the annual ‘Cost of Non-Europe’ in defence to lie between EUR 18 billion and EUR 57 billion (EPRS 2024). This reflects duplication in research and development, non-interoperable equipment portfolios, logistics inefficiencies, and a lack of joint maintenance and training structures (EPRS 2024, 35–45).

These losses occur despite an estimated EU-wide defence expenditure of around EUR 385 billion in 2025 (Consilium 2025). Less than a fifth of procurement is conducted through joint instruments, according to data from the European Defence Agency (EDA) cited in Bain & Company (2025). Therefore, while Europe is increasing spending, the gains are eroded by structural inefficiency, preventing meaningful progress towards capability consolidation.

The Deterrence Capability Gap

Europe’s reliance on outside help and its lack of internal cooperation together create a major gap in its military power, making its defence strategy far less convincing. Credible deterrence requires an autonomous European Union to have high-readiness forces capable of preventing or responding to large-scale aggression without immediate US reinforcement. Estimates by Bruegel and the Kiel Institute suggest that achieving this objective would require EU member states to increase collective annual defence expenditure to approximately 3.5% of GDP (Bruegel Working Papers 2025). This corresponds to an additional EUR 250 billion per year above current spending.

This figure reflects the scale of investment necessary to address shortfalls in air and missile defence, artillery, strategic enablers, and high-readiness land forces. The financial gap, therefore, represents not only an accounting challenge but also the quantitative boundary between current capabilities and the level required for autonomous deterrence.

Rejection of the Readiness 2030 Plan

The main obstacle to closing this gap is fundamentally political. The European Commission’s Readiness 2030 plan, proposed in September 2025, aimed to centralise critical capability procurement through the Community method, thereby reducing duplication and accelerating industrial mobilisation (European Commission 2025). However, the European Council rejected this initiative in October 2025, favouring intergovernmental mechanisms within the European Defence Agency instead (IRIS 2025). Retaining control over procurement decisions preserves national sovereignty, but it also means that the EU will continue to waste up to EUR 57 billion each year due to poor coordination. Moreover, this failure prevents the EU from closing its EUR 250 billion annual defence shortfall and from tackling the challenge set out by the NSS.

The 2025 US National Security Strategy (NSS) further exposed the power imbalance within the transatlantic alliance. Despite increased spending, Europe is not achieving commensurate military gains. The USD 68 billion reliance on US arms, the EUR 57 billion in annual waste, and the EUR 250 billion defence gap all demonstrate that vulnerability is now permanently embedded in Europe’s security structure.

Bibliography

1. Bain & Company (2025) Difesa europea: svolta epocale da 375 ad oltre 600 miliardi di euro. Available at: https://www.bain.com/it/about-bain/media-center/press-releases/italy/202322/Difesa-europea-svolta-epocale-da-375-ad-oltre-600-miliardi-di-euro-E-anche-in-Italia-opportunita-per-private-equity-e-imprese/
2. Consilium (2025) EU defence in numbers. Available at: https://epthinktank.eu/2025/10/08/eu-defence-funding/
3. European Commission (2025) Proposal for a Readiness 2030 Plan. Available at: https://economy-finance.ec.europa.eu/economic-forecast-and-surveys/economic-forecasts/spring-2025-economic-forecast-moderate-growth-amid-global-economic-uncertainty/economic-impact-higher-defence-spending_en
4. European Parliamentary Research Service (EPRS) (2024) Improving the quality of European defence spending: Cost of non-Europe report. PE 762.855. Available at: https://www.europarl.europa.eu/thinktank/en/document/EPRS_STU(2024)762855
5. IRIS Policy Analysis (2025) Post-NSS Scenarios for EU Defence. Available at: https://www.iris-france.org/en/defence-has-the-european-commission-lost-a-battle-to-the-member-states/
6. Mejino-López, J. and Wolff, G.B. (2025) Europe’s dependence on US foreign military sales and what to do about it. Bruegel Policy Brief 27/2025. Available at: https://www.bruegel.org/policy-brief/europes-dependence-us-foreign-military-sales-and-what-do-about-it
7. US Defense Security Cooperation Agency (DSCA) (2024) Fiscal Year 2024 Edition Historical Sales Book. Available at: https://media.defense.gov/2025/Jul/01/2003746467/-1/-1/1/FY_2024_HISTORICAL_
   SALES_BOOK_COMPLETE.PDF
8. US National Security Strategy (NSS) (2025) National Security Strategy. Washington, D.C.: The White House. Available at: https://www.whitehouse.gov/wp-content/uploads/2025/12/2025-National-Security-Strategy.pdf