On September 12, 2001, the day after the 9/11 attacks, NATO met, and for the first and only time in its history, invoked Article 5. All 18 of the USA's allies pledged support of America’s response to the attacks.
On September 12, 2001, the day after the 9/11 attacks, NATO met, and for the first and only time in its history, invoked Article 5. All 18 of the USA's allies pledged support of America’s response to the attacks.