At AUSA 08 Raytheon displayed a typical payload control display employing such sensors. The display supports multiple video feeds displayed as 'thumbnails'. The operator monitors the area under surveillance on a 3D situational map display, employing the Terrasight interactive 3D map, and video integration tool developed by Sarnoff, presenting the video in a dynamic, 'footprint' over the 3D map. The information displayed by the system provides realistic assessment of the locations, dead zones and visibility of potential targets, as they travel behind land curves, buildings etc.
A staffer sitting in an air conditioned room anywhere in the United States or around the world can use this system to detect infiltrators, and then deploy interdiction directly to the GPS coordinates of the infiltrators, rather than having a crew of agents wandering up and down two thousand miles of fence 24x7 looking for holes and infiltrators.
Yes, we need effective barriers to dissuade illegal entry, but even the most effective barrier can be overcome with sufficient time and tools. Just throwing up a fence isn't enough, no matter how high - it needs to be monitored as well, and it may actually be lower cost to do more effective monitoring on a less effective barrier, instead of less effective monitoring on a more effective barrier.