The virtual border fence was supposed to revolutionize US-Mexico border security. But delays and glitches led Homeland Security Secretary Janet Napolitano to freeze its funding Wednesday.
The viability of a high-tech barrier to detect illegal border crossers remains uncertain, after a pilot project struggles.
In Yuma, Ariz., border patrol agents tout the success of a high triple-and double-layered wall. But such a fence is unlikely to stretch the entire border.