Where the tribe draws the line

The border road and barrier between the United States and Mexico run along the Tohono O’odham Nation in Arizona. An escalating confrontation on Native land southwest of Tucson threatens to upend decades of uneasy cooperation between the Tohono O’odham Nation and the United States. — Anna Watts/The New York Times

THE first fence to slice through the Tohono O’odham Nation was simple barbed wire meant to keep cows from roaming south into Mexico. The second, which rose nearly a century later, was a sturdier steel barricade that stopped smuggler trucks from barrelling north into the United States.

The binational tribe, whose land stretches from Arizona into the Mexican state of Sonora, has long been caught in the middle of disputes over a border between two countries that did not exist when the O’odham’s ancestors first settled there thousands of years ago.