Do you really think that people desperate enough to risk death crossing miles and miles of desert are going to be turned back by a fence? Hell no.
The reason they have to risk death crossing miles and miles of desert is that they are forced to go around the fence of death that Clinton built during Operation Gatekeeper. Building partial fences is just making the coyotes rich and killing poor, desperate people. There are two solutions — tear down the fences entirely and allow free movement of people or build and monitor a complete fence stretching from the Gulf to the Pacific. Either solution will probably cost us taxpayers the same amount.
The real issue is corporate control of the US. The reason there are so many desperate illegals willing to do anything to get here is that big ag pushed NAFTA through in order to open up the Mexican market. The campesinos down there were left with no choice and most of us would do the same if we were in their shoes.