Additionally, armed non-state actors have recently been held accountable to international law with the United Nation’s Security Council’s decision to allow the self-defense principle to be applied against an NSA. Following the terrorist attacks of 9/11, the US and the United Nations debated whether the right of self-defense, as protected by UN Charter Article 51, was applicable to armed non-state actors, in this case Al Qaeda. Article 51 allows for member states to pursue preemptive self-defense if they know that an imminent attack is coming. Many issues still remained concerning the extent to which the potential victim state could retaliate against the armed NSA. This is due to the fact that most armed non-state actors often reside on the territory of a sovereign state, and thus, the sovereign state may also endure a retaliatory or preemptive attack. 9/11 had a significant impact in demonstrating that non-state actors could also be held accountable to international law and were able to contend in the political and military arena alongside states.