"In the post-9/11 security environment, special operations forces (SOF) have proven indispensable. SOF units are light, lethal, mobile, and easily networked with other forces. While the United States and its North Atlantic Treaty Organization (NATO) allies have extensive SOF capabilities, these forces are not formally organized to collaborate with one another. There would be much to gain if U.S. and allied SOF trained to work together: national SOF assets would be improved, obstacles to effective combined operations would be removed, and a coherent Alliance capability would be readily available for NATO. The Alliance can focus and grow its SOF capabilities by providing a selective and small combined 'inner core' of NATO special operations forces for operations, while using an outer network to expand and improve SOF cooperation with interested allies."
Defense Horizons No. 52
National Defense University, Center for Technology and National Security Policy: http://www.ndu.edu/ctnsp/