The illegals don’t settle in areas next to the border. San Diego is safer than Los Angeles because the illegals pass through San Diego on their way to areas to the north. If you go up north Santa Ana, Los Angeles or most parts north watch out for the Mexican gangs. And by the way, the border fence does not stop most of them. They go over the fence, around the fence, under the fence, and through the fence.
With the exception of San Diego..the border cities have poor economies and there isn’t much reason for the worst illegals to stay there. They head north for greener pastures. Just go to the bus terminals in El Paso near the border and see them loaded up and headed all over the country.