Self-defense is authorized under Article 51 of the United Nations Charter.

Self-Defense

The act of protecting oneself from harm using reasonable force, especially from immediate physical threat.

Article 51

A provision in the United Nations Charter that provides a right to countries to engage in self-defense if attacked.

United Nations Charter

The foundational treaty of the United Nations, signed in 1945, outlining the organization's purposes, principles, and the framework for international cooperation and peacekeeping.