The Sierra del Carmen is streaked rose and mauve by late sun. Two hundred feet below me, dividing line between that wild range and me, the Rio Grande runs a muddy green. Deep forest weaves around sand dunes and rock cliffs on the Mexican side, a broad, green swath belying the Chihuahuan desert. Forest stretches to the little village of Boquillas, its earth-colored buildings silent, unlit in the mounting twilight. A donkey brays, but nothing within sight moves, nothing but the river.

Beyond the Sierra del Carmen, further mountains rise like shadows. The shadowed peaks pull low pink clouds to themselves. Sun on the Sierra del Carmen fades into old rose. Old rose leads to night.

What is the silence that brings night to this beautiful, lost country? What is the silence of a river no one crosses; of a country cut off from itself by men with guns who insist on borders? How can land have borders? This country where I sit; that country across the river; it is all the same country, a place where mountains reach down to valleys and rivers and the land stretches out into plains and deserts and farther mountains. The land takes for itself what belongs to the land. Nothing more.

In spring, the hedgehog cactus, hechtia, ocotillo -- all the desert plants -- should be exploding with color, exuberantly present to the desert. But in a spring without rain, flowers refuse to bloom. It is miraculous the Rio Grande carries any water at all. Always handicapped by too many users to the north, even in so dry a year, this river brings life. The flowers may be waiting, but the river nurtures trees along its banks, fish who live in it, javelina and deer and cougars who come to it to drink. Rio Bravo del Norte, the Mexicans call it.

It must be brave to insist on moving through this dry land where it is so little honored as to be drained, exploited, forced into narrow channels as if not worthy of its own bed.

All color is gone now from the Sierra del Carmen, but rock walls and cliffs have lightened beneath the pale blue evening sky. It is darker here on the American side. Is there anyone in Boquillas to notice? When the border was so adamantly closed after 9/11, Boquillas residents who worked in Big Bend National Park (where I sit), or who made crafts and lunches to serve Big Bend tourists crossing the river on Mexican donkeys, were no longer allowed across the border. Most of them left. Left for where? South? Away from the Mexican outback? Or north, somehow crossing the river to this country so tormented by their existence – to mingle with countless others terrified of American border law?

Night falls on Boquillas, whether anyone lives there or not. Day, night, the heat of coming summer hovering, the great wall of mountains, the green river, the night birds I hear in the Bosque below -- all of this exists regardless of the border. I watch night fall from my high rock on the American side of the Rio Bravo del Norte. Rivers do not form borders. They merely make their valleys green. In the dark I hear the river as it makes a looping bend to the west, separating two countries that are the same land. I descend in darkness, crossing a backwater pond where fireflies flicker among tall reeds. Living in the Rocky Mountain West, I have not seen fireflies since I was a child.

How easy it is for me to walk away from Mexico . . .