"The drugs are going to keep coming. The people are going to keep coming. The only thing you can do is contain it as much as possible.
"I say the border is as safe and secure as it can be, but I think people are asking for us to seal the border, and that's unrealistic," he said.
Asked why, he said simply: "That's the nature of the border."
Spagat reported from San Diego; Llorca from El Paso, Texas; Sherman from McAllen, Texas; and Skoloff from Phoenix. Also contributing to this report was AP writer Cristina Silva in Phoenix.
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