In 2015, the U.S. Congress decided it was time to take a public accounting of the U.S. government’s war against al-Qaeda. In that year’s National Defense Authorization Act, Congress mandated:

At CNA, we recently completed that independent assessment and concluded that the current U.S. strategy will not defeat al-Qaeda, and that a renewed approach is needed. After 16 years of war against this group, at a cost of over a trillion dollars and thousands of U.S. military members killed, how can this be?

First, al-Qaeda today is a different organization in a different world compared to 2001. Today, the group is larger, more agile, and more resilient than it was 16 years ago, having evolved from a rigidly hierarchical organization with no more than a few hundred members operating primarily in Afghanistan to a flat, decentralized, and geographically dispersed organization with tens of thousands of members operating in at least ten countries from Niger to Bangladesh.