The Obama administration, trying to avoid getting drawn deeper into Syria's civil war, has pointed to the U.S.-led invasion of Iraq in 2003 as a symbol of what can go wrong when America's military wades into Middle East conflicts.
But experts say the White House is looking at the wrong Iraq war, especially as the U.S. reluctantly considers a no-fly zone over Syria to stop President Bashar Assad from continuing to use his air power to crush rebel forces or kill civilians.
A no-fly zone is a territory over which warring aircraft are not allowed to fly. The U.S. and international allies have enforced them in several military conflicts over the past two decades.
When he took office in 2009, President Barack Obama promised to end the U.S. war in Iraq as an example of refocusing on issues that had direct impact on Americans. By the time the U.S military withdrew from Iraq in 2011, almost 4,500 American soldiers and more than 100,000 Iraqis had died. The war toppled Saddam Hussein but also sparked widespread sectarian fighting and tensions that still simmer.
But when considering a no-fly zone, experts point to 1992, a year after the Gulf War. That's when the U.S. imposed a weakly-enforced no-fly zone over southern Iraq and could not prevent Saddam, a Sunni Muslim, from persecuting and killing hundreds of thousands of Shiites whom he viewed as a political threat.
That failure is now being used as a case in point of why the U.S. should or shouldn't police the Syrian sky to prevent Assad from accelerating a two-year death toll that last week reached 93,000.
The White House is undecided on whether it will impose a no-fly zone over Syria, as some have demanded. Egypt's president, Mohammed Morsi, on Saturday called for a U.N. endorsed no-fly zone.
"We've rushed to war in this region in the past. We're not going to do it here," Obama's chief of staff, Denis McDonough, said Sunday on CBS' "Face the Nation."
Vali Nasr, a Middle East expert and dean of the John Hopkins' School of Advanced International Studies, argued for a no-fly zone "to prevent Assad from completely dominating this war for all practical purposes. And we need to create a no-fly zone to create a safe zone for refugees that Assad can't reach."
Nasr, who held a senior State Department job during the first two years of the Obama administration, said in an interview Friday that there are risks, "but perhaps the risks are exaggerated. And what it showed in Iraq is that it does not have to be a slippery slope into a larger war."
On the flip side, said retired Navy Adm. William Fallon, "there's no way to do this in a standoff — 'We're just here to help, not going to get our hands dirty.'"
Fallon, the former head of U.S. Central Command who helped draw up and carry out the 1992 no-fly-zone in Iraq, said the challenge "is that you'd better be prepared for escalation and expansion of mission."
"The likely expansion will be providing air support for guys on the ground," said Fallon, now on the board of directors at the American Security Project, a nonpartisan think tank started by Secretary of State John Kerry when Kerry was a senator.
Last Thursday, the White House deputy national security adviser Ben Rhodes announced the Obama administration has agreed, after months of hesitation, to start supplying the rebels with upgraded military aid. That decision came as a result of stronger intelligence indicating that Assad has used chemicals weapons against his people multiple times this year.
Rhodes would not detail the type of aid. But military officials and experts said it probably would include small-arms weapons, shoulder-fired anti-tank grenades and ammunition.
That would mark the White House's first lethal shipment to Syria. Until now, the administration has mostly supplied the rebels with military equipment, such as body armor and communications devices, and humanitarian aid to the Syrian people.
Obama has not ruled out imposing a no-fly zone in Syria, Rhodes said.
But, Rhodes said, "people need to understand that not only are there huge costs associated with the no-fly zone, not only would it be difficult to implement, but the notion that you can solve the very deeply rooted challenges on the ground in Syria from the air are not immediately apparent."
Supporters of a no-fly zone in Syria point to the one that was established by NATO over Libya in 2011. It overwhelmed Moammar Gadhafi's air defenses and attacked tanks and military vehicles that threatened civilians.
But European nations have shown little appetite for getting directly involved in Syria, where Assad's forces possess an air defense system made far more robust with Russian-bought weapons than what Gadhafi had.
Last month, Russia acknowledged it has agreed to sell Syria advanced S-300 air-defense missiles, which are considered to be the cutting edge in aircraft interception technology and could make a no-fly zone very costly.
Republican Sens. John McCain of Arizona and Lindsey Graham of South Carolina, have been pushing for a no-fly zone in Syria, and last week said supplying arms and ammunition to rebels is not enough to curb Assad's air power. They raised the option of using cruise missiles, which can be launched from outside of Syria, as one way of securing Syria's air space.
On Sunday, Sen. Saxby Chambliss of Georgia, the top Republican on the Senate Intelligence Committee, agreed. "A no-fly zone may be the, ultimately, tactic that has to be taken," he told NBC's "Meet the Press."
Responded Sen. Mark Udall, D-Colo.: "You know, though, a no-fly zone and other involvement may lead to this slippery slope that others talked about."
Twenty years ago, the U.S. mission in Iraq showed that no-fly zones must be aggressively enforced if they are to work.
Military air units generally need to be working closely with ground forces to make sure that airstrikes and missile attacks hit their intended targets and don't kill civilians.
Fallon said that's how no-fly zones often prompt a mission creep, as deploying air forces can easily turn into a need to send in ground troops. U.S. and European officials vehemently maintain there are no plans to launch a ground war in Syria.
Though fighter jets flew over the vast Iraqi desert every day for more than a decade, they had no help or guidance on the ground, and were unable to stop Saddam from moving his army in to attack Shiites and drain the desert region's vital marshlands, which served as a water lifeline to the local population. Saddam still flew Iraqi helicopters and gunships into the south to crush a rag-tag rebellion.
Iraqi officials estimate at least 200,000 Shiites were killed, and thousands more fled to neighboring Iran, a Shiite state, for refuge.
"The no-fly zone had a limited effect on Saddam's ability to hurt the Shiites," Haider Mansour, a teacher from the Shiite-dominated city of Basra in Iraq's south, said Saturday. "But it increased the suffering of ordinary people because it forced Saddam to dry the marshes."
Nasr said Iraq's majority Shiites never forgot the tepid U.S. support against Saddam during the 1990s. Despite the U.S.-led invasion that overthrew Saddam, Nasr said it's little surprise that Baghdad's Shiite-led government now arguably has stronger ties with Iran than it does with Washington.
The parallels between Iraq and Syria are clear, Nasr said, as are the potential consequences.
"There was an uprising against a dictator who was no friend of ours, and we did not prevent a massacre," Nasr said. He said the U.S. inaction opened the door for Shiite militias and radicalism, and led to Iran's influence in Baghdad "because nobody else supported Shiites against Saddam."
"And so, one can say, 'We can tolerate hundreds of thousands of people being killed,'" Nasr said. "But there are consequences to it."
Fallon said the major flaw in the Iraqi no-fly zone was the lack of a clear plan or, even, an ultimate goal.
"At the time, it sounded OK," he said. "It was certainly much less dramatic, it wasn't necessarily going to be a shooting war, it was going to be to 'Keep Saddam under control.'
"But what was the end state? Nobody knew. But we did it anyway. And so this thing went on forever," Fallon said. "And the longer it went on the more unpalatable it was to stop it. And was it effective? No. Did it stop Saddam? No."
The current Iraqi government has ignored several U.S. requests for help in stopping Iranian flights of supplies to Syria.
Creating an effective no-fly zone in Syria would require fighter jets or drones equipped with radar and weapons as well as other surveillance planes, said national security analyst Anthony Cordesman at the Center for Strategic and international Studies. He predicted it probably would have to be done without U.N. support, and it may lead to U.S. troop deaths.
Associated Press writer Sameer N. Yacoub in Baghdad contributed to this report.
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