A significant number of Puerto Ricans participate as members and work for the U.S. Armed Services, largely as National Guard members and civilian employees. The size of the overall military-related community in Puerto Rico is estimated to be 100,000 individuals. This includes retired personnel. Fort Buchanan has about 4,000 military and civilian personnel. In addition, approximately 17,000 people are members of the Puerto Rico Army and Air National Guards, or the U.S. Reserve forces. Puerto Rican soldiers have served in every U.S. military conflict from World War I to the current military engagement known by the United States and its allies as the War against Terrorism.