OP 22: The US Army on the Mexican Border: A Historical Perspective

Since the mid-19th century, the United States has frequently employed the US Army on its southern border to perform various roles in support of the Nation—from outright war, to patrolling the border, to chasing bandits while securing persons and property on both sides of the border, and most recently to supporting civil law enforcement and antidrug efforts. Events since 9/11, such as the recent deployment of National Guard Soldiers to the Mexican border, are only the latest manifestation of this long tradition. This 22nd Occasional Paper in the Combat Studies Institute (CSI) Long War Series, The US Army on the Mexican Border: A Historical Perspective, by CSI historian Matt M. Matthews, reviews the lengthy history of the US Army on the Mexican border and highlights recurring themes that are relevant to today’s ongoing border security mission.