Hector Holguin remembers when it was possible to cross the thin strip of the Rio Grande dividing the US and Mexico in the border town of El Paso by tram. Growing up, he would hop on the car to cross into ­Juárez and visit relatives or go to the barber, as Mexicans travelled the other way into the US to buy televisions and clothes.

Border patrol agents conducted inspections on the now defunct streetcar and the economies of both border towns thrived.