Santos fires up his computer and shows an image he snapped in the cemetery of a nearby town. There, there, he points as he enlarges a section of the photo. Slowly a skull-shaped blur floats into view against the black of the night—a ghost, he believes. The border is haunted by ghosts—the hundreds who die each year from heat and cold, the ones killed in car wrecks as the packed vans of migrants flee the Border Patrol, and the increasing violence erupting between smugglers and the agents of Homeland Security. Whenever heat is applied to one part of the border, the migration simply moves to another part. The walls in southern California drove immigrants into the Arizona desert and, in some cases, to their deaths. We think of walls as statements of foreign policy, and we forget the intricate lives of the people we wall in and out.

Emanuel Castillo Erúnez, 23, takes crime and car wreck photos for El Mirador. He went north illegally when he was 17, walked a few days, then was picked up and returned to Mexico. He sits on a bench in the plaza, shielded by a New York Yankees cap, and sums up the local feeling about the wall simply: "Some are fine with it, some are not." He thinks of going north again, but then he thinks of getting caught again. And so he waits.

There is a small-town languor about Naco, Sonora, and the wall becomes unnoticeable in this calm. The Minutemen and National Guard terrify people. At the Hospedaje Santa María, four people wait for a chance to go over the wall and illegally enter the wealth of the United States. It is a run-down, two-story building, one of many boarding houses for migrants in Naco. Salvador Rivera, a solid man in his early 30s, has been here about a year. He worked in Washington State, but, when his mother fell ill, he returned home to Nayarit, Mexico, and is now having trouble getting past the increased security. He left behind an American girlfriend he can no longer reach.

"For so many years, we Mexicans have gone to the U.S. to work. I don't understand why they put up a wall to turn us away. It's not like we're robbing anybody over there, and they don't pay us very much."

But talk of the wall almost has to be prompted. Except for those engaged in smuggling drugs or people, border crossers in Naco, Sonora, continue to enter through the main gate, as they always have. They visit relatives on the other side, as they always have. What has changed is this physical statement, a big wall lined with bright lights, that says, yes, we are two nations.

Jesús Gastelum Ramírez lives next door to the wall, makes neon signs, and looks like Willie Nelson. He watches people climb the wall and he understands a reality forgotten by most U.S. lawmakers—that simply to go through the wire instantly raises a person's income tenfold. Gastelum knows many of his neighbors smuggle people, and he understands.