A three tier line of defense including double fences (some concrete and steel), guard towers, flood lights infrared cameras, under ground sensors, patrol roads, night scopes, horse patrols, ATV patrols, 16 helicopters, fixed wing aircraft, unmanned aerial vehicles, trucks, and a ratio of 32 guards per mile were incorporated.
It was successful in reducing the number of immigrants crossing at that sector. Most just went further East to cross, but still about two hundred thousand are caught each year trying to cross, and another estimated 30 to 40 thousand make it across undetected. They dig under, climb over and break through the fences. Thats an average of 454 to 606 per mile per year.
Extrapolating the cost/benefit results of Operation Gatekeeper to the entire 105,000 mile coastline and land borders of the United States, at 32 guards per mile at $175,000 per guard, it would cost $588 Billion Dollars per year and still 47 to 63 Million people could cross undetected into the U.S. each year.
The Inspector General's Report On Operation Gatekeeper found in part:"For the first six months of 1996, the average daily low estimate of effectiveness was 17 percent and the average daily high estimate was 27 percent. The lowest estimate was 10 percent, the highest, 41 percent."
How confident was the government that Operation Gate Keeper would seal the border? Here's what our friend from the Terrorism Commission said at the time:
There are no legitimate studies showing that it is possible to seal the border. The problems of illegal immigration are going to have to be addressed at the destination of the border jumpers.