BAGHDAD — Curling through the desert, wind rattling its marshes, the Tigris once brought so much life to this city, where spices and silks were loaded on wooden boats bound for Basra and beyond. Shiites lived with Sunnis, Christians and Jews, but today, as in other times, unity splinters in bloodshed.
The river's bridges have turned into escape routes for families fleeing sectarian death squads. Some head one way, others go the opposite direction, and many fear that if full-scale civil war erupts, the Tigris will act as a green line, separating Sunni-dominated west Baghdad from the Shiite-controlled east.
The shoes of Akram Mustafa tell the story of a dividing city; the orange dust from the clay tennis courts is fading on them. One of his country's top-ranked tennis players, Mustafa seldom plays these days. Getting to his club along the Tigris would mean crossing from his eastern neighborhood of Sadr City into streets guarded by Sunnis.
"I haven't been out of Sadr City in five or six months," Mustafa said. "Each day we stand in the same place talking the same talk to the same people. We have nothing."
Travel west across the river to the Sunni neighborhood of Amiriya and listen to Fatima Omar: "I have a best friend who's leaving the country in six or seven weeks, and I can't go visit her because she lives in a Shiite neighborhood."
With each explosion, with each firefight, Omar's geography shrinks.
"We are prisoners of the city," she said.
Conditions that lead Pentagon generals to say civil war is close are already polarizing many neighborhoods. Although Shiites and Sunnis still live side by side in some places, about 200,000 Iraqis, most of them from Baghdad, have left their mixed neighborhoods and taken refuge in communities where they can live among their own. In July, the Baghdad morgue reported more than 1,800 violent deaths.
A widening war would strike at the city's religious complexities, which have grown over time: Each sect has holy sites in the other's territory, and neighborhoods such as Kadhimiya, a Shiite stronghold in west Baghdad, and Adhamiya, a Sunni pocket in the east, would be surrounded by enemies.
"The national character of Iraqis doesn't want the city divided," said Adnan Yassin, a sociologist at Baghdad University. "Sunni and Shiite have lived together for centuries. They've married one another. How can you divide this?"
Gone are the days of walking hand-in-hand with your lover along the Tigris, hearing the clack of backgammon through the scent of fish grilling beneath the moon. Sunni car bombers drive into Shiite marketplaces; Shiite death squads move through the night, leaving Sunni bodies in alleys and date palm groves. Some people carry two identity cards, one for who they really are, the other a lie to save them from death that often waits behind a suspicious gaze.
The Tigris rolls between the rage on both sides. Boatmen pull fish and bodies from the water. Iraqi and U.S. forces race along the banks, and sometimes a child, standing in the wrong place, will vanish in the dust of mortar rounds. It all gets whispered about along the Tigris, as if the river were a thread stitching together the vignettes of a city of 6 million that has lived on the edge for way too long.
Baghdad has become a sinister parlor game of unmasking affiliations with subtle and not so subtle questions: Where does your family come from, north or south? Who is your uncle? What tribe do you belong to? It is a place where death squads call the family of someone they've kidnapped and ask: Is he a Shiite, or a Sunni? A wrong answer can mean a trip to the morgue to identify a body streaked with acid burns and drill holes.
Jabbar Dulaimi bobs along in this vortex. A calm man with neatly combed hair, he's a councilman in Mansour, a once mixed neighborhood that is increasingly dominated by Sunnis. More than 150 shops are shuttered on 14th of Ramadan Street, many of them after owners received fliers from insurgents telling them to close or die. Garbage blows on sidewalks, rats scurry, sewage backs up in homes.
Dulaimi's cellphone buzzes and blinks with calls from constituents, but what can he do if fear keeps his municipal crews from work?
"I can't even pick up the garbage anymore," said Dulaimi, a Sunni. "One ward leader in Mansour told me, 'I can't send my trash collectors in there, they'll kill them.' "
Sectarian bloodshed has escalated since February, when Sunni insurgents attacked a Shiite shrine in Samarra. In the old arithmetic of Iraq, Sunni Arabs, many of them Baathists who benefited under Saddam Hussein, despised the American occupation. The majority Shiites wanted the U.S. to help rebuild a country. Now the Shiites are in control, and their death squads have forced Sunnis to inch toward the Americans for cover.