Ask a cattle man!! I am Not one but I know a few. and have had some cattle. If you want to keep your cows in a fence, you must keep them Well Feed and watered. The problem on the border is that people can cross the border and earn more money here than they can in Mexico. "Greener grass on the other side of the fence" If we can stop this. This will be a deterent. Fence Crawlers . Ask a Cattle man. Some Cows always seem to climb over fences. Electric fences seem to work for those. A two layer fence with a restricted zone between. Backed up with a Vehicle Access road running parralel. Seems like a Good anology. The more you work with Cattle the more you see the similarities between them. The Ultimate answer is to make the conditions on the Mexican border so great that the advantage of crossing is reduced. However reducing advantages on this side of the border so that they are less than the southern side is a Reduction of our oppurtunity. I Sincerly Hope we ca Avoid that!!