Brookings Institution: a nonprofit public policy organization based in Washington, DC. http://www.brookings.edu/
RAND: The RAND Corporation is a nonprofit institution that helps improve policy and decisionmaking through research and analysis. http://www.rand.org
Strategic Studies Institute: U.S. Army War College's institute for geostrategic and national security research and analysis. http://www.strategicstudiesinstitute.army.mil/
Center for Strategic and International Studies (CSIS): A bipartisan, nonprofit organization headquartered in Washington, DC, CSIS provides strategic insights and policy solutions to decisionmakers in government, international institutions, the private sector, and civil society. http://csis.org/
Council on Foreign Relations (CFR): is a nonprofit and nonpartisan membership organization dedicated to improving the understanding of U.S. foreign policy and international affairs, based in NYC. http://www.cfr.org/
Center for Naval Analyses (CNA): CNA is a non-profit research organization that operates the Center for Naval Analyses and the Institute for Public Research. It is based in VA. http://www.cna.org/
Center for a New American Security (CNAS): As an independent and nonpartisan research institution, informs the national security leaders of today and tomorrow. Established in 2007, it is located in Washington, DC. http://www.cnas.org/
U.S. Marine Corps, Center for Irregular Warfare (CIW)The CIW is the central Marine Corps organization for identifying, coordinating, and implementing irregular warfare capability development initiatives across all elements of DOTMLPF in order to increase, improve, and enhance Marine Corps capabilities and capacities to conduct operations across the spectrum of war against irregular threats https://www.mccdc.usmc.mil/CIW/index.html