NATO rules allow members to fight wars without permission

The 1949 treaty that created NATO is famous for Article 5, the 'all for one' clause that binds members together in defense. However, Article 3 contains a less discussed provision that preserves the absolute right of individual nations to act alone. This means a member state can launch a unilateral military strike or engage in a foreign conflict without seeking a vote or even notifying its allies in advance. While the alliance provides a massive security umbrella, it does not legally function as a leash on the world's most powerful militaries.