The number of Iraqis fleeing their homes has soared since the American troop increase began in February, according to data from humanitarian groups, accelerating the partition of the country into sectarian enclaves. Despite some evidence that the so-called troop surge has improved security in certain areas, sectarian violence continues and American-led military operations have brought new fighting, driving fearful Iraqis from their homes at much higher rates than before the tens of thousands of additional troops arrived, the studies show.
The data track what are known as internally displaced Iraqis: those who have been driven from their neighborhoods and seek refuge elsewhere in the country rather than fleeing across the border. The effect of this vast migration is to drain religiously mixed areas in the center of the country, sending Shiite refugees toward the overwhelmingly Shiite areas to the south and Sunnis toward majority Sunni regions to the west and north.
Though most displaced Iraqis say they would like to return, there is little prospect of their doing so. One Sunni Arab who was driven out of the Baghdad neighborhood of southern Dora by Shiite snipers said she doubts that her family will ever return to the house.
"There is no way we would go back," said the woman, 26, who gave her name only as Aswaidi. "It is a city of ghosts. The only people left there are terrorists."
Statistics collected by the Iraqi Red Crescent Organization, indicate that the total number of internally displaced Iraqis has more than doubled, from 499,000 to 1.1 million, since the start of the surge in February.
Those figures are broadly consistent with data compiled independently by an office within the UN that specializes in tracking wide-scale dislocations. That office, called the International Organization for Migration, found that in recent months the rate of displacement within Baghdad itself, where the surge is focused, has increased by a factor of as much as 20, although part of that rise could stem from improved monitoring of displaced Iraqis by the government in the capital.
The new findings suggest that while sectarian attacks have dropped in some neighborhoods, the influx of troops and the intense fighting they have brought with them is at least partly responsible for what a UN migration office report calls the worst human displacement in Iraq's modern history.
The findings also indicate that the sectarian tension the troops were meant to defuse is still intense in many places throughout the country: 63 percent of the Iraqis surveyed by the UN said they fled their neighborhoods because of direct threats to their lives, and over 25 percent because they had been forcibly removed from their homes.
The demographic shifts could favor those who would like to see Iraq partitioned into three semi-autonomous regions: a Shiite south and a Kurdish north sandwiching a Sunni territory in between.
Overall, the scale of this migration has put so much strain on Iraqi governmental and relief offices that some provinces have refused to register any more displaced citizens, or will accept only those whose families are originally from the area. But Rafiq Tschannen, chief of the Iraq mission for the migration office, said that in many cases, the ability of extended families to absorb displaced relatives was also stretched to the breaking point.