国际战略研究所-Defending-Europe-scenario_51页_2mb

Summary of Defending Europe: Scenario-based capability requirements for NATO's European members

Core Content

This report by the International Institute for Strategic Studies (IISS) presents an independent, open-source analysis of how NATO's European members would need to reconfigure their military capabilities in the event of a U.S. military withdrawal from NATO. The study is based on two specific scenarios set in the early 2020s, focusing on the protection of global sea lines of communication (SLOCs) and the defense of European NATO territory against a state-level attack.

The report does not aim to predict future conflicts or prescribe specific actions to be taken by European governments. Instead, it uses plausible scenarios to generate force requirements and assess the ability of European NATO members to meet them, based on current military inventories and procurement data.

Main Scenarios and Force Requirements

Scenario 1: Protection of Global Sea Lines of Communication (SLOCs)

• Background: The U.S. withdraws from NATO and abandons its global maritime presence and protection role.
• Objective: To maintain a stable maritime-security environment in European waters and beyond, ensuring the free flow of international trade and protection of maritime infrastructure.
• Force Requirements:
  • Enhanced maritime presence in the eastern Atlantic, Mediterranean, Indian Ocean, and Western Pacific.
  • Increased group-deployment capabilities beyond current NATO and EU forces.
  • A fleet in being or high-readiness forces to support deterrence and escalation management.
• Key Assumptions:
  • European navies will continue to fulfill their national and international commitments.
  • There is no expectation of nuclear weapons use in this scenario.
  • The NATO Command Structure will remain in place, with European members filling the gaps left by the U.S. withdrawal.
• Estimated Cost: Between $94 billion and $110 billion to close capability gaps.

Scenario 2: Defence of European NATO Territory Against a State-Level Attack

• Background: Tensions between Russia and NATO members Lithuania and Poland escalate into war after the U.S. leaves NATO.
• Objective: To deter and repel Russian aggression, including the occupation of Lithuania and the seizure of Polish territory.
• Force Requirements:
  • A significant increase in land forces, particularly in heavy armoured formations.
  • A robust NATO Command Structure to coordinate operations.
  • Establishment of Operation Eastern Shield and Operation Eastern Storm.
• Key Assumptions:
  • The U.S. is no longer a NATO member by the end of 2021.
  • The NATO Response Force (NRF) and Very High Readiness Joint Task Force (VJTF) continue to exist.
  • France takes over the lead for the Enhanced Forward Presence (EFP) battalion in Poland.
• Estimated Cost: Between $288 billion and $357 billion to close capability gaps.

Key Findings

• European Capabilities: European NATO members currently lack sufficient modern and capable forces to address the scenarios, especially in the area of heavy armoured formations.
• NATO Command Structure: The study highlights the critical importance of the NATO Command Structure for complex operations, suggesting that without it, European states may struggle to manage the required tasks.
• Strategic Autonomy Debate: The report serves as a reality check for the ongoing debate on European strategic autonomy, emphasizing the need to focus on actual capabilities rather than institutional changes.
• Timeframe for Recapitalization: If funding is available, it would take up to 20 years to recapitalize military forces across all domains, with significant progress expected at the 10- and 15-year marks.
• U.S. Withdrawal Impact: The U.S. withdrawal leads to a shift in the global posture of the U.S. Navy, with a focus on the Pacific and a reduced presence in Europe and the Atlantic.

Implications for Europe’s Defence Debate

• The report underscores the vulnerability of European security in the absence of U.S. military support.
• It suggests that while the U.S. remains a crucial player in NATO’s defense, European members must take greater responsibility for their own security.
• The study also highlights the complexity of maritime operations and the need for sustained investment in naval capabilities, especially in response to Russian naval activities and the degradation of global maritime security.
• The concept of NEMO (NATO/EU Maritime Objective) is introduced as a coordinated plan to enhance maritime presence and security across key regions.

Conclusion

The report provides a detailed analysis of the potential military shortfalls that would occur if the U.S. were to withdraw from NATO, emphasizing the need for European strategic investment and enhanced cooperation between NATO and the EU. It outlines the financial and operational challenges involved in achieving this, and underscores the long-term nature of capability development. The findings are intended to support informed policy dialogue in both European and transatlantic contexts.