"In addition to participation in the war in Afghanistan,

Posted on: February 25, 2022 at 11:05:04 CT

NATO’s response to the 9/11 attacks under Article 5 included Operation Eagle Assist, in which NATO aircraft helped patrol the skies over the United States for seven months between 2001 and 2002, and Operation Active Endeavour, in which NATO naval forces were sent to perform counterterrorism activities in the Eastern Mediterranean. Operation Active Endeavour, which began in October 2001 and later expanded to the entire Mediterranean region, didn’t conclude until 2016."

https://www.history.com/news/nato-article-5-meaning-history-world-war-2