The United States Border Patrol is the mobile, uniformed law enforcement arm of the U.S. Customs and Border Protection (CBP) within the Department of Homeland Security (DHS). It was officially established on May 28, 1924 by an act of Congress passed in response to increasing illegal immigration. As mandated by this Act, the small border guard in what was then the Bureau of Immigration was reorganized into the Border Patrol. The initial force of 450 officers was given the responsibility of combating illegal entries and the growing business of alien smuggling.
Since the terrorist attacks of September 11, 2001, the focus of the Border Patrol has changed to detection, apprehension and/or deterrence of terrorists and terrorist weapons. Although the Border Patrol has changed dramatically since its inception over 75 years ago, its overall mission remains unchanged: to detect and prevent the illegal entry of aliens into the United States. Together with other law enforcement officers, the Border Patrol helps maintain borders that work – facilitating the flow of legal immigration and goods while preventing the illegal trafficking of people and contraband.
The Border Patrol is specifically responsible for patrolling the 6,000 miles of Mexican and Canadian international land borders and 2,000 miles of coastal waters surrounding the Florida Peninsula and the island of Puerto Rico. Agents work around the clock on assignments, in all types of terrain and weather conditions. Agents also work in many isolated communities throughout the United States.