EU Common Security and Defence Policy

Legal Foundations: Articles 42–46 TEU

The Common Security and Defence Policy (CSDP) constitutes an integral part of the Common Foreign and Security Policy under Title V of the Treaty on European Union. Articles 42 to 46 TEU, introduced in their current form by the Treaty of Lisbon, provide the constitutional framework for the CSDP, defining its objectives, institutional architecture, operational capabilities, and decision-making procedures. Article 42(1) TEU establishes that the CSDP provides the Union with an operational capacity drawing on civilian and military assets from Member States, which the Union may use for peace-keeping, conflict prevention, and the strengthening of international security in accordance with the principles of the United Nations Charter.

The mutual defence clause in Article 42(7) TEU provides that if a Member State is the victim of armed aggression on its territory, the other Member States shall have towards it an obligation of aid and assistance by all the means in their power, in accordance with Article 51 of the UN Charter. This clause, which operates alongside the NATO collective defence commitment under Article 5 of the North Atlantic Treaty, is a legally binding obligation of solidarity among EU Member States. The clause does not affect the specific character of the security and defence policy of certain Member States, including those that are neutral or non-aligned. The solidarity clause in Article 222 TFEU provides a complementary framework for the Union and its Member States to act jointly in the event of a terrorist attack or natural or man-made disaster.

The Petersberg Tasks

The Petersberg tasks, originally adopted by the Western European Union in 1992 and incorporated into the EU Treaty framework by Article 43 TEU, define the scope of CSDP military and civilian missions. The tasks encompass: joint disarmament operations; humanitarian and rescue tasks; military advice and assistance tasks; conflict prevention and peace-keeping tasks; tasks of combat forces in crisis management, including peace-making and post-conflict stabilisation; and support for third countries in combating terrorism in their territories. The Lisbon Treaty expanded the Petersberg tasks to include the use of civilian and military capabilities in all phases of crisis management, including joint disarmament operations and post-conflict stabilisation.

CSDP missions are conducted under the political control and strategic direction of the Political and Security Committee (PSC), a permanent Council committee composed of Member State ambassadors that monitors the international situation and contributes to the definition of EU policies. The European Union Military Committee (EUMC), composed of the Member States’ Chiefs of Defence represented by their military representatives, provides military advice and recommendations to the PSC and exercises military direction of CSDP military operations. The European Union Military Staff (EUMS) provides early warning, situation assessment, and strategic planning for CSDP missions.

Civilian and Military Missions

The EU has launched over 35 CSDP missions and operations since 2003, including both civilian and military deployments across Europe, Africa, the Middle East, and Asia. Civilian missions focus on capacity-building, rule of law, police training, security sector reform, and monitoring, typically operating under a civilian mandate with non-military personnel. Notable civilian missions include EULEX Kosovo (the largest civilian CSDP mission, focusing on rule of law), EUAM Ukraine (advisory mission for civilian security sector reform), and EUPOL COPPS (police mission in the Palestinian Territories).

Military operations include peace-keeping, peace-enforcement, and stabilisation missions. EUFOR ALTHEA in Bosnia and Herzegovina, launched in 2004, provides a military presence to support the Dayton Peace Agreement. EUNAVFOR MED IRINI enforces the UN arms embargo on Libya. EUNAVFOR ATALANTA protects against piracy off the coast of Somalia. EUTM Mali provided military training and advice to the Malian armed forces. Military operations are typically conducted under a UN Security Council mandate and in cooperation with NATO and other international partners.

The Civilian Planning and Conduct Capability (CPCC) serves as the operational headquarters for civilian missions, while military operations may be conducted through national headquarters, the Operations Centre in Brussels, or through NATO’s command structures under the Berlin Plus arrangements.

Permanent Structured Cooperation (PESCO)

Permanent Structured Cooperation (PESCO) , established by Article 42(6) and Article 46 TEU and Protocol No 10, provides a framework for those Member States that meet higher defence capability criteria and have made more binding commitments to one another in the area of defence cooperation. PESCO was formally launched in December 2017 with 25 participating Member States, each of which undertook to increase defence investment, develop collaborative defence capabilities, contribute to CSDP missions, and enhance the readiness and availability of their armed forces.

PESCO operates through a governance framework comprising the Council (decision-making), the High Representative (overall coordination), and the PESCO Secretariat within the European External Action Service. Participating Member States submit annual National Implementation Plans demonstrating progress towards their commitments. PESCO projects cover a wide range of capability areas, including the European Medical Command, the Cyber Threats and Incident Response Information Sharing Platform, Maritime Surveillance, and Military Mobility. The conditionality and governance mechanisms of PESCO are designed to ensure that participation translates into concrete improvements in European defence capabilities.

The European Defence Fund

The European Defence Fund (EDF) , established by Regulation (EU) 2021/697 with a budget of approximately €8 billion for the 2021–2027 multiannual financial framework, provides EU funding for collaborative defence research and capability development. The EDF is the first EU programme to fund defence research and development directly at the European level, marking a significant step in the integration of European defence industrial policy.

The EDF comprises two distinct pillars. The research pillar funds collaborative defence research projects addressing emerging threats, disruptive technologies, and future defence capabilities. The capability pillar co-funds the development of defence capabilities jointly developed by consortia of at least three entities from at least three Member States or associated countries. Funding is available for prototyping, testing, qualification, and certification of defence products and technologies. The EDF includes incentives for cross-border participation by small and medium-sized enterprises and for projects that contribute to the EU’s strategic autonomy.

The EDF is complemented by the European Defence Industrial Development Programme (EDIDP) and by PESCO projects, which benefit from simplified access to EU funding and from the regulatory flexibilities provided by the European Defence Agency (EDA) in the areas of procurement and armaments cooperation.

Institutional Architecture: Foreign Affairs Council and High Representative

The CSDP is governed by a distinctive institutional architecture that reflects the intergovernmental character of EU foreign and security policy. The Foreign Affairs Council (FAC) , composed of the Member States’ ministers for foreign affairs, defence, and development, adopts CSDP decisions by unanimity under Article 42(4) TEU. The High Representative of the Union for Foreign Affairs and Security Policy, who also serves as Vice-President of the Commission, is responsible for the conduct of CFSP and CSDP, including proposing CSDP decisions, chairing the Foreign Affairs Council, representing the Union externally, and coordinating the consistency of EU external action.

The European External Action Service (EEAS) , established by Council Decision 2010/427/EU, functions as the diplomatic service of the Union and provides the administrative and analytical support for CSDP decision-making. The EEAS manages the EU’s delegations worldwide, coordinates crisis response, and supports the High Representative in the conduct of CFSP and CSDP.

Conclusion

The EU Common Security and Defence Policy has evolved from a declaratory framework into an operational policy domain encompassing military and civilian crisis management missions, defence capability development, and defence industrial cooperation. The legal framework established by the Lisbon Treaty, combined with institutional innovations including PESCO and the European Defence Fund, provides the basis for deepening European defence cooperation within the broader context of the Union’s external action. The continuing development of CSDP reflects the evolving security challenges facing the Union and its Member States.