The Obama administration's preparations on Syria this week raise many thorny questions about the risks associated with launching a punitive strike against Bashar Assad's regime over the alleged use of chemical weapons.
Below are some of the main questions, along with answers compiled from McClatchy's own reporting, other news reports, think tank analyses, and the conclusions of experts on Middle East policy, national security and chemical weapons.
This primer is based on the latest information available, and some of the answers could change, as developments are coming fast in the buildup to an intervention. It's important to remember that the Obama administration has yet to officially announce any course of action, though officials have issued a clear warning that Assad would be held "accountable."
Q: Why are we considering military action in Syria?
A: The Obama administration says the Syrian regime must be punished for past use and deterred from future use of chemical weapons in the country's civil war.
For months, the White House has believed that Syria was using such arms on a small scale, but the trigger for this current buildup was an Aug. 21 attack that killed hundreds of people – the precise number is unclear – in an eastern suburb of Damascus. To the administration, that was an inexcusable crossing of a "red line" President Barack Obama set; he risks losing credibility if his warning is seen as a bluff.
The White House is stressing that any action would be punitive for the alleged use of chemical weapons, but not intended to remove the regime. Such a response after the war has entered a third year and killed more than 100,000 doesn't satisfy the Syrian opposition, which has long asked for foreign military help in toppling Assad.
The U.S. stance also doesn't reassure critics of intervention who recall that the U.S. joined a NATO-led campaign in Libya on similar humanitarian grounds and ended up participating in the removal of Moammar Gadhafi.
Q: Is it certain that chemical weapons were used?
A: The United States and European allies such as France and Britain have said they're certain of chemical weapons use in Syria, and they hold the Assad regime responsible because it has control over the stocks and delivery systems.
Apart from classified intelligence – some of which may be released publicly this week – the U.S. points to witness accounts and amateur videos that show dozens of dead and dying Syrians.
Chemical weapons experts generally agree that the high number of casualties and symptoms exhibited in the videos are consistent with the use of some type of chemical agent, but they're being cautious in their pronouncements until they see results from samples collected by a U.N. inspection team that's currently in Syria.
The U.N. team's mandate is just to determine whether chemical weapons were used – but not to assign culpability.
The Syrian regime denies using chemical weapons and repeatedly has said the rebels were the ones employing such methods. And a mystery remains: Why would the regime use chemical weapons, which almost certainly would invite Western intervention, when the U.N. inspectors had just arrived in the country?
Q: What legal basis is there for an attack on Syria?
A: Britain drafted a U.N. Security Council resolution that would condemn the use of chemical weapons and authorize "necessary measures" to protect Syrian civilians.
However, the United States already has rejected the Security Council route, saying it's doomed to fail because Assad ally Russia is "intransigent" on Syria. Russia and China, which hold veto power, have blocked previous resolutions targeting the Syrian regime.
The White House instead is trying to build a coalition supporting military intervention outside of a Security Council resolution, as when NATO acted in Kosovo. An internal U.N. report later found that the intervention was legitimate but not legal.
Q: What kind of attack should we expect, and when?
A: The aim of the attack is to "deter and degrade" – but, significantly, not to destroy – Syria's large chemical weapons stockpile. This policy goal will be carried out via a limited strike by cruise missiles fired from U.S. Navy destroyers in the eastern Mediterranean Sea off Syria's coast, defense officials say.
While four of the warships are in place, one of them has enough missiles to inflict significant damage, but one or more of the other destroyers could engage in the attack as well. Pentagon officials have tried to rebut reports that the U.S. attack will be staggered over several days, suggesting there will be a single attack or burst of attacks in a shorter period of time.
So far, the warnings have been the opposite of the "shock and awe" threats that preceded the initial U.S. assault on Iraq in March 2003. In its 2011 military strike against Libya's Gadhafi, the U.S. launched 212 Tomahawks as part of an ostensibly humanitarian mission that ended up collapsing the regime.
The United States is unlikely to target the chemical weapons themselves, either at ammunition depots or in mobile convoys that Assad has kept in motion, for fear of releasing nerve gas that could kill civilians. More likely targets are the elite Syrian units that safeguard and transport the weapons.
There's only speculation about the timing of the attack. It could come any time now, but it might be held up by logistical or diplomatic snags, such as the necessity for waiting until after the British Parliament meets in an emergency session later this week, or until U.N. inspectors leave Syria.
Q: Does Congress support U.S. action in Syria?
A: Congress appears to be of a mixed mind on Syria. Hawkish lawmakers such as Sens. John McCain, R-Ariz., and Lindsey Graham, R-S.C., have been critical of Obama's handling of Syria and have urged U.S. intervention. But an unusual coalition of liberal and conservative lawmakers – from liberal Rep. Zoe Lofgren, D-Calif., to tea party favorite Rep. Justin Amash, R-Mich. – appears to be building in Congress that's demanding Obama to seek congressional approval before intervening militarily in Syria.
Obama faced heavy criticism for joining the NATO-led operation in Libya in 2011 without congressional approval. Then, as now, the administration is arguing that it doesn't need congressional approval because the War Powers Resolution only requires "consultation" if the mission is limited in scope, with American forces only serving in a supporting role.
Nevertheless, U.S. officials are reaching out to lawmakers, who don't return from recess until Sept. 9, in hopes of fewer ruffled feathers this time around.
Q: Is there international support for an intervention?
A: British Prime Minister David Cameron has stated flatly that chemical weapons were used by the Syrian regime and that there must be consequences, though he wants any mission to be limited in scope and have legal cover. Also, it's only been a month since a parliamentary backbench vote went against arming rebels by a 114-1 tally, and members will meet in a special session this week with no guarantees of returning in favor of intervention.
There's no waffling with France, where President Francois Hollande said his nation stands "ready to punish those who took the heinous decision to gas innocents." The Germans have made it clear that they will support what others do but would play only a very minor role.
Turkey was the first major Muslim partner to pledge participation in a coalition against Syria, regardless of U.N. approval.
Nudged by influential Saudi Arabia, the 22-member Arab League issued a statement that was interpreted as tacit endorsement for international punishment for Assad's regime, though the language was vague on that point and big-member states such as Egypt have serious concerns about intervention.
Q: Will there be retaliation from Syria or its allies?
A: Syria Foreign Minister Walid al-Moallem warned this week that Syria would defend itself by any means available, adding that the regime could "surprise others" who are planning an attack on the country.
It's impossible to say how the regime would – or could – respond to an intervention, especially with no clear idea of the scope or duration of an attack. Its forces are busy fighting rebels inside the country, but Syrian officials have suggested that retaliation could come in parts of Turkey or neighboring Lebanon, home to its key ally Hezbollah.
Hezbollah and Iran have far greater ability to respond, but also a more complex political calculation to make as they seek to protect their own regional interests from the Syrian morass. However, Hezbollah and Iran both maintain the ability to strike targets around the world and to do so largely anonymously, as the Israelis have accused them of doing in last year's suicide bombing of tourists in Bulgaria.
Q: Is there popular support for intervention among Americans?
A: The images of dead and dying Syrians from last week's alleged chemical weapons attack sparked global outrage but didn't appear to change the American public's opposition to military intervention, according to the findings from a Reuters/Ipsos poll that was conducted Aug. 19-23 and released this week.
About 60 percent of Americans said Obama shouldn't intervene in Syria's civil war, while just 9 percent favored action. More Americans would support U.S. intervention if the use of chemical weapons were to be confirmed – with 25 percent in favor, 46 percent opposed — but that's a decline since Aug. 13, when a previous Reuters/|Ipsos poll asked the same question and got responses of 30.2 percent in support of intervention to 41.6 percent opposed.
Q: Is there a precedent for such an attack?
A: The closest case in recent history to the drama now unfolding in Syria may be Kosovo, in 1999. The United States, its NATO allies and other friendly countries could not win outright Russian agreement at the U.N. Security Council to approve an air bombardment against Serb forces in Kosovo, but acted anyway, in the name of preventing a humanitarian catastrophe.
However, the Kosovo intervention came on the heels of a number of U.N. resolutions on Kosovo, the military operations were undertaken by the NATO alliance, with every state having a veto, and the object was regime change – important differences from the Syria case.
In terms of the punishment inflicted, Obama may be recalling two military operations in 1998 – one to avoid, and one as a possible, though flawed, model.
In August 1998, after operatives of Osama bin Laden's al Qaida network exploded bombs at two U.S. embassies in East Africa, President Bill Clinton ordered the Navy to fire cruise missiles at sites in Afghanistan in hopes of killing bin Laden. Bin Laden escaped harm, burnished his legend, recruited more followers and prepared for what would be the 9/11 attacks.
The other example occurred in December 1998, when Clinton staged "Operation Desert Fox" and the U.S. military, together with Britain, bombed nearly 100 military targets in Iraq, with the aim to degrade Saddam Hussein's military capabilities in response to his violations of U.N. resolutions. Saddam stayed in power until his regime crumbled in the U.S.-led invasion of Iraq in 2003.
Q: What's the role of the Syrian opposition?
A: Both the Syrian military and political opposition are complaining that they're being cut out of planning for a strike. The State Department counters that senior officials are in touch with Gen. Salim Idriss, the U.S. point person for relatively moderate rebel factions. And Ambassador Robert Ford, the envoy to Syria who now serves outside the country, is in Istanbul meeting with Syrian opposition leaders.
In all likelihood, the U.S. wants to limit the role of the Syrian opposition, which on the political side has proven ineffectual and fractious, and on the rebel side has become dominated by al Qaida-linked jihadist fighters.
A scenario the White House doesn't want to see: the Assad regime collapsing and Syria being overrun with Islamist extremists. But that's a real risk, analysts say, and a foreign military intervention could hasten that depending on how big a strike is.
Q: How else is the United States involved in the Syrian conflict?
A: While Obama until now has resisted significant military engagement in Syria, his administration has contributed more than $1 billion in humanitarian aid since the crisis began, according to State Department figures.
The aid includes food, medical and hygiene assistance, as well as special programs to address gender-based violence and to care for vulnerable women and children, especially the 1.9 million refugees who've fled the conflict to dismal camps and overwhelmed communities in neighboring countries such as Jordan, Lebanon and Iraq.
Q: Will this drag the U.S. into another long war in the Middle East?
A: "Mission creep," the military's term for the expansion of operations beyond the original goal, is perhaps the No. 1 concern for U.S. officials and lawmakers, especially after more than a decade fighting fierce wars in Iraq and Afghanistan.
There's no real popular support for U.S. involvement in Syria, and the sectarian makeup and precarious location of the country means that any escalation has the potential to suck in neighboring countries and inflame the entire Middle East. U.S. officials worry that even a limited military action will tether the United States to the conflict, which is why the White House is taking pains to present potential action on Syria as focused punishment only for chemical weapons use.
James Rosen and William Douglas contributed from Washington, Matthew Schofield from Berlin, Roy Gutman from Istanbul and special correspondent Mitchell Prothero from Beirut.
Strike on Syria: What can we expect?
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