MATAMOROS, MEXICO — A butter yellow sun rose over the crowded tent camp across the river from Texas and a thick heat baked the rotten debris below, a mixture of broken toys, human waste and uneaten food swarming with flies.

Clothing and sheets hung from trees and dried stiff after being drenched and muddied in a hurricane the week before.

As residents emerged from the zipper-holes of their canvas homes that morning in August, some trudged with buckets in hand toward tanks of water for bathing and washing dishes. Others assembled in front of wash basins with arms full of children’s underwear and pajamas. They waited for the first warm meal of the day to arrive, though it often made them sick.

The members of this displaced community requested refuge in the United States but were sent back into Mexico, and told to wait. They came there after unique tragedies: violent assaults, oppressive extortions, murdered loved ones. They are bound together by the one thing they share in common — having nowhere else to go.

“Sometimes I feel […]