Article 51 of the United Nations Charter affirms the inherent right of states to self-defense, individually or collectively, in response to an armed attack. Though the article is situated within the law governing the resort to force it intersects with both international human rights law (IHRL) and international humanitarian law (IHL) once force is employed. The law of armed conflict, IHL and IHRL are complimentary; all addressing individual and civilian dignity in peace and war.
Military responses undertaken under this article may lead to civilian casualties, forced displacement, and the curtailment of rights such as life, liberty, and security of person. The legality of such force under Article 51 does not absolve states of their parallel obligations under IHRL and IHL. As affirmed by the International Court of Justice (ICJ) in its Advisory Opinion on the Legality of the Threat or Use of Nuclear Weapons (1996) and Democratic Republic of the Congo v Uganda (2005), IHL continues to apply even when a state lawfully uses force in self-defense, illustrating that the right to self-defense does not immunize states from accountability under other bodies of international law.
In the context of Iraq and the Kurdistan Region of Iraq (KRI), Article 51 has been invoked by various states, notably in the US-led interventions against non-state actors like ISIS. These operations, while framed as collective self-defense, raised critical concerns about civilian protection and the proportionality of force, especially in densely populated areas. This is despite serious violations, such as the US forces did with the detained prisoners of war in Abu Gharib. For the KRI, caught between terrorist threats and foreign interventions, the interplay of Article 51 with human rights protections remains a pressing legal and ethical challenge.
In sum, while Article 51 provides a lawful basis for the use of force, it must be exercised within the constraints of IHRL and IHL to ensure accountability and civilian protection.