WASHINGTON — Suicide bombers in Iraq are overwhelmingly foreigners bent on destabilizing the government and undermining American interests there, two independent studies have concluded.
The studies report that the number of suicide bombings in Iraq has now surpassed those conducted worldwide since the early 1980s. The findings suggest that extremists from throughout the region and around the world are fueling Iraq's violence.
"The war on terrorism — and certainly the war in Iraq — has failed in decreasing the number of suicide attacks and has really radicalized the Muslim world to create this concept of martyrs without borders," said Mohammed Hafez, a visiting professor at the University of Missouri in Kansas City and the author of one of the two studies.
Hafez, whose new book is "Suicide Bombers in Iraq," has identified the nationalities of 124 bombers who attacked in Iraq. Of those, the largest number — 53 — were Saudis. Eight apiece came from Italy and Syria, seven from Kuwait, four from Jordan and two each from Belgium, France and Spain. Others came from North and East Africa, South Asia and various Middle Eastern and European countries. Only 18 — 15 percent — were Iraqis.
In the second study, Robert Pape, a University of Chicago professor who runs the Chicago Project on Suicide Terrorism, identified the nationalities of 55 suicide bombers in Iraq. Sixteen were Saudis, seven were Syrians and five were Algerians. Kuwait, Morocco and Tunisia each supplied three bombers. Thirteen — 24 percent — were Iraqi Sunni Muslims.
Hafez and Pape said Iraqi Shiite Muslims hadn't carried out suicide attacks so far and instead had restricted their role in the sectarian violence to militia activity.
Pinning down the nationalities of suicide bombers can be tricky because they leave few physical remains, and extremist groups often don't claim the attacks until much later. The U.S. military says it does some DNA testing to investigate the bombers' identities.
Both researchers relied on extremist Web sites, "martyr" videos, news reports and statements to compile the data on nationalities. Hafez also gathered some information from online chats and discussion forums.
U.S. intelligence estimates based on interviews with detainees and captured documents indicate that most suicide bombers in Iraq are non-Iraqi, said a senior defense official who can't be named because of departmental rules
Suicide attacks more than doubled each year from the U.S.-led invasion in 2003 to 2005, Pape said. In 2006, he said, they jumped just under a third. The American military has reported more than 1,400 since January 2004. Before the U.S.-led invasion, there had been no suicide bombings in Iraq.
Pape attributed the attacks to the presence of some 150,000 American troops in the region.
The notion that most of the suicide bombers are foreigners engaged in a global movement is exaggerated, he said, since about 75 percent come from the Arabian Peninsula, which is close to the U.S. forces in Iraq.
"The Arabian Peninsula isn't that big: It's somewhat bigger than Texas," Pape said. "The Americans have all the capability and are right there. That's what allows terrorist leaders to build a sense of urgency."
After losing safe havens in Afghanistan, Pakistan and Europe, militant organizations needed a new base for their operations, Hafez said. U.S. intelligence analysts, however, have concluded that al Qaida has built new training camps along the Afghan-Pakistani border, and that the group al Qaida in Iraq operates for the most part independently.
According to Hafez, extremist groups in Iraq conduct suicide bombings against fellow Muslims rather than U.S. troops to destabilize the fledgling government and spark sectarian warfare.
The groups' objectives in Iraq are different from "other places like in the Palestinian-Israeli conflict or in Lebanon," he said.
In Lebanon, Shiite suicide bombers helped drive U.S., British, French, Italian and Israeli troops out of the country with a series of attacks. Sunni Palestinian suicide bombers have attacked in Israel and the Palestinian territories in an effort to loosen Israel's grip on what they say are Arab lands.
There's widespread agreement that Saudis are represented more heavily than any other nationality among the bombers, said Assaf Moghadem, a research fellow at Harvard University who studies suicide bombers' motivations. Insurgent groups sometimes recruit Saudis because of their relative prosperity, he said.
The ultra-conservative brand of Sunni Islam that's prevalent in Saudi Arabia also accounts for the large number of Saudis who participate in suicide bombings and the insurgency in Iraq, said Mike Davis, a University of California at Irvine professor who wrote a recent history of car bombs.
"The religious current in modern Islam that encourages this kind of sectarian attitude toward the Shiites is the religious orthodoxy enshrined in Saudi Arabia," Davis said.
Most experts say that while the American presence in Iraq has radicalized Muslims, withdrawing the troops may not stem the number of suicide attacks, at least not right away.
Extremist groups in Iraq have a common goal of expelling foreign occupiers and destabilizing what they see as a U.S.-controlled government, Pape said. But if the U.S. withdraws, insurgent organizations probably will engage in a bloody power struggle, he added.
"If we stay, that tends to encourage people to flock to Iraq," Hafez said. "Leaving will mean genocidal violence for the Iraqi people. It will mean a failed Iraqi state. The jihadists will declare, `We drove out America.' "