Legal justification for the strike that killed Osama bin Laden

The justification for the 2011 U.S. raid that killed Osama bin Laden rests on three overlapping legal frameworks: (1) the right of self-defense under international law, (2) the law of armed conflict, and (3) U.S. domestic authorization for the use of force.

1. International law: self-defense (UN Charter Article 51)

Under international law, bin Laden was treated as a lawful military target because he directed ongoing armed attacks against the United States. The U.S. position was that Article 51 of the UN Charter preserves a state’s right to use lethal force in self-defense against ongoing or continuing attacks. The raid was framed as part of an ongoing armed conflict with al-Qaeda, and killing its commander was presented as a legitimate act of self-defense.

2. Law of armed conflict: targeting a combatant

Under the law of armed conflict (LOAC), a state engaged in an armed conflict may target enemy combatants without a prior obligation to attempt capture. Al-Qaeda was treated as an organized armed group engaged in hostilities, and bin Laden, as its leader, was considered to have a continuous combat function. On that basis, he was deemed a lawful target regardless of whether he was armed at the precise moment of the raid.

The core idea is that, within an armed conflict, the targeting of a combatant leader is not considered an unlawful “assassination” but a wartime targeting operation.

3. U.S. domestic law: Authorization for Use of Military Force (AUMF) 2001

After the 9/11 attacks, the U.S. Congress passed the Authorization for Use of Military Force (AUMF) in 2001. This statute empowered the President to use force against those responsible for the attacks and associated forces. Since bin Laden was the acknowledged leader of al-Qaeda and had publicly claimed responsibility for 9/11, the U.S. government argued that the raid fell squarely within this authorization.

In this view, the President had explicit domestic legal authority to use lethal force against al-Qaeda leadership, including bin Laden.

4. Sovereignty and the operation in Pakistan

The most controversial aspect of the raid was that it took place on Pakistani territory without prior notification or consent. Two main legal arguments were invoked:

• Unwilling or unable doctrine: The idea that a state may use force in another state’s territory if that state is unwilling or unable to address a threat emanating from its soil.
• Self-defense overriding sovereignty: The claim that when a serious and ongoing threat exists, the right of self-defense can justify a limited violation of another state’s territorial sovereignty.

On this basis, the U.S. argued that Pakistan was either unwilling or unable to neutralize bin Laden and that the raid was a necessary and proportionate act of self-defense.

5. Was it an assassination?

Critics sometimes described the operation as an “assassination,” but many legal experts rejected that characterization. In their view, assassination refers to killing outside the context of armed conflict or in violation of applicable law. Because the U.S. framed the situation as an ongoing armed conflict with al-Qaeda, and bin Laden as a lawful combatant target, the raid was characterized as a lawful wartime targeting operation rather than an illegal assassination.

6. Summary table

Legal basis	Core argument
International self-defense	Ongoing armed attacks by al-Qaeda justified the use of lethal force under Article 51 of the UN Charter.
Law of armed conflict	Bin Laden, as leader of an organized armed group, was a lawful combatant target.
U.S. AUMF (2001)	Congress authorized the President to use force against those responsible for 9/11 and associated forces.
Unwilling/unable doctrine	Pakistan was treated as unwilling or unable to neutralize the threat, permitting a limited use of force on its territory.