Maps
Library of Congress - American Revolution and Its Era: Maps and Charts of North America and the West Indies, 1750-1789
Library of Congress - Civil War Maps
Library of Congress - Hotchkiss Map Collection - Confederate Army Maps
Library of Congress - Rochambeau Map Collection - American Revolution
US Military Academy - Department of History Campaign Atlases
Military News
Canadian Forces College - Spotlight on Military News and International Affairs
Defense Technology International - Ares
John Robb - Global Guerillas
Kettle Creek - Defense and the National Interest
Kings College London - Kings of War
Michael P. D'Alessandro - Naval Open Source Intelligence
StrategyWorld - StrategyPage
Thomas P.M. Barnett - Weblog
Philosophers
Christopher Bassford - Clausewitz.com
Sonshi - Sun Tzu The Art of War
Reference Libraries
George Washington University - National Security Archive
GlobalSecurity.org - GlobalSecurity.org
US Air Force - Air Force Publishing
US Air Force - Historical Research Agency
US Army - Center of Military History
US Army - Command and General Staff College Combined Arms Research Library
US Army - Heritage and Education Center
US Army - Training and Doctrine Digital Library
US Army - War College Strategic Studies Institute
US Marines - History and Museums Division
US Marines - Small Wars Center of Excellence
US Navy - Naval Historical Center
War Colleges
British Army - Royal Military Academy Sandhurst
Canada - Canadian Forces College
US Air Force - Air War College
US Army - Army War College
US Army - Command and General Staff College
US Navy - Naval War College