Identify one major international operation led by NATO.

The ISAF mission in Afghanistan is a significant international operation led by NATO, initiated in 2001 following the 9/11 attacks. The mission was aimed at providing security and stability in Afghanistan while assisting the Afghan government in rebuilding and establishing a functioning state in the wake of the Taliban's ousting. This operation represented a collaborative effort by NATO member states and partner nations to respond to a global security threat and was pivotal in demonstrating NATO's capability to conduct expeditionary operations beyond its traditional European and North Atlantic area.

Operation Enduring Freedom was primarily a U.S.-led initiative focused on combating terrorism and did not fall under NATO leadership in its initial phases. Operation Desert Storm was a U.S.-led coalition operation during the Gulf War that was not a NATO mission. Operation Unified Protector was a NATO-led operation in Libya in 2011 that aimed to enforce United Nations Security Council Resolutions, but the ISAF mission in Afghanistan had a longer-term commitment and complexity, highlighting NATO's evolution into a global security organization.