International Armed Conflict (IAC)

Primary reference(s)

ICRC, 2016. Commentary on the First Geneva Convention. International Committee of the Red
Cross (ICRC). Accessed 14 January 2020.

Additional scientific description

Common Article 2 of the Geneva Conventions of 1949 defined International Armed Conflict (IAC) as, “all cases of declared war or of any other armed conflict which may arise between two or more of the High Contracting Parties, even if the state of war is not recognized by one of them.” IAC “exists whenever there is a resort to armed force between States” (ICTY, 1995) and “can always be assumed when parts of the armed forces of two States clash with each other” (Schindler, 1979). (The Geneva Conventions refer to States that are party to the Conventions as ‘High Contracting Parties’.)

International armed conflict is conceptually broader and more flexible than the notion of war between States, because IAC is based on objective and factual criteria and does not rely on the formal declaration of war (ICRC, 2016). By extension, the termination of IAC is based on evidence on the ground and not a ceasefire or peace agreement (ICRC, 2016). Article 6(2) of the Fourth Convention stipulates that the Convention ceases to apply when there is objective evidence of “the general close of military operations,” and the International Criminal Tribunal for the former Yugoslavia (ICTY) ruled that International Humanitarian Law “extends beyond the cessation of hostilities until a general conclusion of peace is reached” (ICTY, 1995: para. 70).

The category of IAC encompasses a broad range of international hostilities, including, but not limited to:

• “All cases of partial or total occupation of the territory of a High Contracting Party, even if the said occupation meets with no armed resistance” (ICRC, 1949, Article 2[2]).
• “An unconsented-to invasion or deployment of a State’s armed forces on the territory of another State – even if it does not meet with armed resistance” (ICRC, 2016, para. 223).
• “Armed conflicts in which peoples are fighting against colonial domination, alien occupation or racist regimes” (ICRC, 1977, Additional Protocol I, Article 1[4], para. 1).
• “Minor skirmishes between the armed forces, be they land, air or naval forces” (ICRC, 2016, para. 237).

Armed forces and non-military agencies acting on behalf of the State may be involved in the means and methods of IAC, and the use of armed force may be directed against a State’s armed forces, territory, population, or military or civilian infrastructure (ICRC, 2016).

Metrics and numeric limits

The identification and classification of IAC is not conducted by a central authority, and there is no minimum threshold of intensity or duration for a confrontation to be considered a situation of IAC (ICRC, 2016). There are numerous academic conflict datasets available that provide their own operational thresholds for the minimum number of annual fatalities for IAC events and trends to be included. For example, two of the most influential academic conflict datasets, the Uppsala Conflict Data Program (Uppsala Universitet, no date) and the Correlates of War (The Correlates of War Project, no date) apply annual conflict-related fatality thresholds of 25 and 1000, respectively.

Examples of drivers, outcomes and risk management

Armed conflict carries immediate and severe impacts on human lives, health, and dignity: “Increasing numbers of civilians have been killed, wounded, treated without dignity, arbitrarily detained and/or separated from their families. They have been targeted on purpose, forced to leave their homes, and deprived of their basic rights as human beings, such as the right to supplies essential to their survival” (ICRC, 1999).

In situations of armed conflict, international humanitarian law aims to protect people, the environment (e.g., Article 55 of ICRC 1977), livelihoods, infrastructure, education systems, health systems, and cultural objects and property, to name a few (ICRC, 1999).