UVALDE, Texas—Rancher John Sewell recently picked up a pamphlet that had fallen from the backpack of an illegal immigrant who was trespassing on his property near Uvalde, Texas—about 50 miles from the U.S.–Mexico border. On one side is a map that details transport routes from Panama to the United States. It pinpoints in great detail where migrants can find shelter or get medical help along the way. The other side is full of useful information, in Spanish, including how to more safely travel through forests and jungles, find shelter, get medical help, and deal with immigration authorities. It was published by the Red Cross and is titled “Messages of Self-Help for Migrants.” The pamphlet crosses a line beyond providing life-saving information to facilitating illegal immigration, according to Jessica Vaughan, director of policy studies at the Washington-based Center for Immigration Studies. “It’s practically a road map or a TripTech for an …