Abstract
We test two sets of alternative hypotheses about the demographic composition of the U.S. armed forces. We analyse individual-level data of two national representative samples covering the period 1979-2008. We find that, in contrast to the accepted wisdom, the U.S. military no longer primarily recruits individuals from the most disadvantaged socio-economic backgrounds. Technological, tactical, operational and doctrinal changes have led to a change in the demand for personnel. As a result, on different metrics such as family income and family wealth as well as cognitive abilities, military personnel are on average like the average American citizen or slightly better.