Aggression

The act of aggression is one of the most serious crimes as it undermines the existence of the State, its territorial integrity and therefore the core principles of international law. It is now prohibited through both international public law and international criminal law.

The act of aggression can:

1.  engage the responsibility of the State before the International Court of Justice and give rise to sentences and reparations.
2. engage the individual criminal responsibility before the International Criminal Court which may also take measures of individual compensation.

Nuremberg

The Nuremberg trial has introduced the act of planning, preparing, initiating, or waging a war of aggression as a crime against peace, engaging the criminal responsibility of perpetrators.

United Nations

• The United Nations Charter states that “all Members shall refrain in their international relations from the threat or use of force against the territorial integrity or political independence of any state, or in any other manner inconsistent with the Purposes of the United Nations.” Nonetheless, resort to armed force is authorized in two circumstances:

1. In the case of self-defense, individual or collective, authorized by Article 51 of the UN Charter;
2. In the context of collective measures of security adopted by the UN Security Council (Art. 42 of the UN Charter).

• The Security Council is the sole body competent to determine the existence of any threat to the peace, breach of the peace, or act of aggression, without giving any definition of aggression.
• In 1974 the General Assembly defined aggression as “the use of armed force by a State against the sovereignty, territorial integrity or political independence of another State, or any other manner inconsistent with the Charter of the United Nations.” The following acts constitute acts of aggression, regardless of a declaration of war, though they are not exhaustive:

1. The invasion or attack by the armed forces of a State of the territory of another State, or any military occupation, however temporary, resulting from such invasion or attack, or any annexation by the use of force of the territory of another State or part thereof;
2. Bombardment by the armed forces of a State against the territory of another State or the use of any weapons by a State against the territory of another State;
3. The blockade of the ports or coasts of a State by the armed forces of another State;
4. An attack by the armed forces of a State on the land, sea, or air forces, or marine and air fleets, of another State;
5. The use of armed forces of one State that are within the territory of another State with the agreement of the receiving State, in contravention of the conditions provided for in the agreement or any extension of their presence in such territory beyond termination of this agreement;
6. The action of a State in allowing its territory, which is placed at the disposal of another State, to be used by that other State for perpetrating an act of aggression against a third State;
7. The sending by or on behalf of a State of armed bands, groups, irregulars, or mercenaries to carry out acts of armed force against another State of such gravity as to amount to the list of acts listed above, or its substantial involvement therein.

This definition is based on three criteria:
(1) the act of aggression must be perpetrated by a State and can engage the responsibility of such State;
(2) it implies the use of armed force; and
(3) it must reach a level of sufficient gravity in order to be qualified as such by the Security Council.

International Criminal Court

The Rome Statute provided in its Article 5 that “the Court shall exercise jurisdiction over the crime of aggression once a provision is adopted." In 2010 the Assembly of State Parties adopted a resolution that included a definition of the crime of aggression. The definition of the crime of aggression is mainly inspired by the UN General Assembly resolution 3314 of 1974. The definition is contained in the new Article 8 bis of the Statute:

1. “For the purpose of this Statute, ‘crime of aggression’ means the planning, preparation, initiation or execution, by a person in a position effectively to exercise control over or to direct the political or military action of a State, of an act of aggression which, by its character, gravity and scale, constitutes a manifest violation of the Charter of the United Nations.
2. For the purpose of paragraph 1, ‘act of aggression’ means the use of armed force by a State against the sovereignty, territorial integrity or political independence of another State, or in any other manner inconsistent with the Charter of the United Nations. Any of the following acts, regardless of a declaration of war, shall, in accordance with United Nations General Assembly resolution 3314 (XXIX) of 14 December 1974, qualify as an act of aggression:
3. The invasion or attack by the armed forces of a State of the territory of another State, or any military occupation, however temporary, resulting from such invasion or attack, or any annexation by the use of force of the territory of another State or part thereof;
4. Bombardment by the armed forces of a State against the territory of another State or the use of any weapons by a State against the territory of another State;
5. The blockade of the ports or coasts of a State by the armed forces of another State;
6. An attack by the armed forces of a State on the land, sea or air forces, or marine and air fleets of another State;
7. The use of armed forces of one State which are within the territory of another State with the agreement of the receiving State, in contravention of the conditions provided for in the agreement or any extension of their presence in such territory beyond the termination of the agreement;
8. The action of a State in allowing its territory, which it has placed at the disposal of another State, to be used by that other State for perpetrating an act of aggression against a third State;
9. The sending by or on behalf of a State of armed bands, groups, irregulars, or mercenaries, which carry out acts of armed force against another State of such gravity as to amount to the acts listed above, or its substantial involvement therein.”