Remarks at an Arria-Formula Meeting on Upholding the Collective Security System of the UN Charter (via VTC)

Ambassador Jeffrey DeLaurentis
Acting Alternate Representative for Special Political Affairs
United States Mission to the United Nations
New York, New York
February 24, 2021


Good afternoon, colleagues. I would like to thank the Mexican Mission for hosting this meeting. I would also like to join others in thanking Professor Modirzadeh for her presentation. We read with great interest her and Dustin Lewis’s 2019 study on Article 51 of the UN Charter.

The inherent right to use force in the exercise of individual or collective self-defense against non-state actors is well-established. For centuries, States have invoked the right of self-defense to justify taking action on the territory of another State against non-State actors. Since the terrorist attacks on September 11, 2001, 19 different States have identified or referred to non-State actors in their Article 51 notifications.

But the United States agrees that the doctrine of self-defense is not a license to wage war globally or to disregard the borders and territorial integrity of other States.

In particular, the exercise of the inherent right of self-defense is subject to the customary international law requirements of necessity and proportionality. “Necessity” requires States to consider whether actions in self-defense that would impinge on another State’s sovereignty are necessary – that is, whether measures short of force have been exhausted or are inadequate to address the threat posed by the non-State actor emanating from the territory of another State.

This consideration entails an assessment of whether the territorial State is able and willing to mitigate the threat emanating from its territory and, if not, whether it would be possible to secure the territorial State’s consent before using force on its territory against a non-State actor. But this legal standard does not dispense with the importance of respecting the sovereignty of other States.

Applying the standard ensures that force is used on foreign territory without consent only in certain exceptional circumstances. Specifically, those in which a State cannot or will not take effective measures to confront a non-State actor that is using the State’s territory as a base for attacks and related operations against other States. This leaves a law-abiding nation only the choice to respond in self-defense.

Turning to the content of Article 51 notifications, Article 51 does not impose any requirement on what, specifically, must be included other than a description of the measures taken in self-defense. State practice has varied with respect to the content of Article 51 notifications.
Although the Article 51 notification may include a detailed legal justification for the measures taken, this is not required; the notification is intended only to put the Security Council on notice of the measures taken.

Finally, the United States favors transparency. The United States submits Article 51 notifications with the expectation that they will be publicly available. We note that all Article 51 notifications are electronically available on the UN’s documentation website, to all UN Member States and the public at large in addition to being noted in the Repertoire of the Practice of the Security Council as that publication is updated.

We are prepared to work with other Council Members through the Informal Working Group on Documentation and Procedure and with the UN Secretariat to explore ways to make such letters more easily accessible.

Thank you.