Sunni Muslim extremists who sympathize with the Al Qaeda terror network intend to make Iraq their next battleground, as in Bosnia (search), Chechnya (search) and Soviet-occupied Afghanistan, say U.S. intelligence officials monitoring their communications.
American intelligence experts estimate that several hundred to several thousand violent Islamic militants have entered Iraq to make war on U.S. and British forces. And the collective decision by so-called jihadists across the Islamic world suggests more are on the way, if they can make it to Iraq.
Whether enough will arrive to create a sustained guerrilla war is not yet clear, U.S. officials said.
"Iraq is emerging as the next jihad venue for Sunni extremists," according to one recent U.S. intelligence report obtained by The Associated Press. "Similar to Afghanistan, Chechnya and Bosnia, many extremists are rallying to join the fight."
For now, however, the greatest threat in Iraq remains the surviving members of Saddam Hussein's secular rule who are conducting guerrilla war and are suspected of carrying out terror bombings since the U.S. invasion, intelligence officials say.
There are scattered signs of contacts and cooperation between some foreign jihadists and Saddam's supporters, the officials say. But this appears to have emerged only recently and is not regarded as evidence of prewar collusion between Saddam and Al Qaeda.
Still, U.S. officials acknowledge they don't have a good handle on what Americans face in Iraq. Major bombings, including the Aug. 19 strike at the United Nations headquarters in Baghdad, remain unsolved.
Intelligence officials acknowledge the jihadists don't operate with a single will. The officials use the term — jihad means holy war — to describe Sunni Muslim extremists willing to travel from their home countries to fight. Many operate under the umbrella of the Al Qaeda network. Some are members, others sympathizers.
The intelligence officials try to get a sense of attitudes by watching Internet chat rooms, Web sites and publications, and by following the words of religious leaders with a known extremist bent. Recent messages from Ayman al-Zawahri (search), Usama bin Laden's chief surviving deputy, have called for attacks against Americans in Iraq.
In previous conflicts that drew significant numbers of jihadists, the fighters used guerrilla tactics against technologically superior occupying forces. They became experienced fighters and established relationships with like-minded men from other countries.
The Soviet occupation of Afghanistan was the genesis of Al Qaeda. During the 1980s, Islamic fighters traveled to Afghanistan to fight alongside the Afghan resistance. After the Soviets left in 1989, bin Laden, who financed some of those fighters' travel and training, founded Al Qaeda as a support organization for veterans.
Over time, the international connections hardened as bin Laden pledged to continue the Afghan jihad around the world.
Two of the fighters who took part in defending Bosnian Muslims from Serbs and Croats in 1995 were young Saudis named Nawaf al-Hazmi and Khalid al-Mihdhar. They went on to play an organizing role in the Sept. 11 attacks and died on the hijacked plane that crashed into the Pentagon.
In Bosnia and Afghanistan, the invading forces eventually left, after the jihadists found themselves on the same side as the United States and other Western powers. The fighting in Chechnya has led to terrorist attacks in Moscow.
The man running extremist operations in Iraq is thought to be Abu Musab Zarqawi (search), a Jordanian whom the CIA describes as a senior associate of bin Laden.
Zarqawi has been inside Iraq in recent months but his current whereabouts are unknown. He has supporters in Jordan, some of whom have probably moved to Iraq to take part in attacks on U.S. forces.
He is also tied to Ansar al-Islam (search), a Kurdish Islamic extremist group, U.S. officials say. The group was based in northern Iraq, in a region outside of Saddam's control, before the war, and was bombed by U.S. warplanes during the fighting. Its members can also move into nearby Iran, according to intelligence officials.
Now, surviving Ansar members serve as guides and fixers for foreigners entering Iraq, officials say.
"Ansar al-Islam is closely tied to Al Qaeda and is an extension of the network in Iraq," the U.S. intelligence report says. On Tuesday, U.S. officials confirmed the capture of a man they described as the No. 3 operative in Ansar.
Jihadists began entering Iraq in significant numbers during the summer, officials have said. L. Paul Bremer, the U.S. administrator in Iraq, said last month that 19 Al Qaeda members were among some 248 foreign fighters detained by U.S. forces in the country.
"There are some dangerous people in Iraq," White House spokesman Scott McClellan said Tuesday. "Iraq has become the central front in the war on terrorism."
About half the foreign fighters are from Syria, with large numbers also from Iran and Yemen, Bremer said.
Elements of some of the bombings may be indicative of the work of Al Qaeda and its allies.
The Aug. 7 car bombing at the Jordanian Embassy in Baghdad may suggest the involvement of Zarqawi, who is accused of plotting other strikes against his home country, U.S. officials say.