The United States Border Patrol is much more than a glorified checkpoint force, rounding up illegal aliens and smugglers as they make their way across our northern and southern borders. In the wake of September 11, 2001, the mission of the Border Patrol has been fundamentally redefined, with emphasis shifting from stopping the flow of drugs and illegal immigration to the critical mission of protecting our vast borders from terrorist infiltration. Agents patrol some 8,000 miles of United States borderlands in helicopters, four-wheel-drive trucks, motorcycles, ATVs, and snowmobiles, as well as on horseback, by bicycle, and on foot. These dedicated men and women learn to clear buildings like the most highly skilled SWAT teams, and their knowledge of immigration law rivals that of many attorneys. The job is lonely, hard and dangerous. Agents often operate in remote areas where their backup can be hours away, forcing them to rely on their instincts and training to confront criminals, and, on many occasions, to save their own lives.