That's not to say Arizonans don't have a right to be upset when Mexicans trespass across private land on a regular basis. But you could solve that problem by making it easier for them to immigrate legally.
It's also worth remembering that this used to be a rare phenomenon. What made it common was not a new avalanche of people coming to the United States without permission. It was a federal offensive to intercept them in major border cities where they used to arrive.
"Closing the old entry points diverted them into places which didn't have many undocumented immigrants before," Princeton University sociologist Douglas Massey told me. Instead of sneaking into San Diego or El Paso, they are prone to entering somewhere else—often in the Arizona desert, where the chance of being caught is lower.
April 28, 2010
Arizona Immigration (III)
"If immigrants suddenly disappeared and the country became immigrant-free (and illegal-immigrant free), crime rates would likely increase." From "How Immigration Crackdowns Backfire" by Steve Chapman in Reason.com"