Add Yahoo as a preferred source to see more of our stories on Google. U.S. Senator Kyrsten Sinema, I-Ariz., right, visits the U.S.-Mexico border in Somerton, Ariz., near the Cocopah Indian Reservation ...

When Donald Trump stepped off his plane and onto the Texas tarmac, he approached a pool of reporters awaiting his arrival. “Nice weather. A very beautiful day,” he said. “But a very dangerous border.