The Obama administration says there is no doubt that Syrian President Bashar al-Assad was responsible for a recent chemical weapons attack near Damascus, which Syrian opposition forces and human rights groups allege killed hundreds of civilians.

Secretary of State John Kerry called the attack a “moral obscenity” and the White House has vowed to respond – though the question of how is still under debate.

The Syrian government denies using nerve agents on its own people and has allowed U.N. weapons inspectors into the country to investigate.

As the U.S. weighs its options and rallies its allies for a possible military strike, Stanford scholars examine the intelligence and discuss the implications of military action against Syria. Those scholars are:

• Martha Crenshaw, one of the nation’s leading experts on terrorist organizations and a senior fellow at the Center for International Security and Cooperation and the Freeman Spogli Institute for International Studies
• Thomas Fingar, former chairman of the National Intelligence Council and currently the Oksenberg-Rohlen distinguished fellow at FSI
• Thomas Henriksen, a senior fellow at the Hoover Institution specializing in U.S. foreign policy and author of the book, “America and the Rogue States”
• Anja Manuel a CISAC affiliate, co-founder and principal at RiceHadleyGates LLC, a strategic consulting firm, and lecturer in Stanford's International Policy Studies
• Allen S. Weiner, a CISAC affiliated faculty member and co-director of the Stanford Program in International Law at the Stanford Law School
• Amy Zegart, an intelligence specialist who is the CISAC co-director and a senior fellow at the Hoover Institution

Does a military strike on Damascus risk further inflaming terrorists operating in Syria who hate the United States?

Crenshaw: I doubt that an American military response to the Assad regime's use of chemical weapons will make al-Qaida and affiliates hate us any more than they already do. The effect on wider public opinion in the Arab and Muslim worlds is what we should be thinking about. As the U.N. noted in a recent report, al-Qaida has a strong presence in Syria and is attracting outside recruits. The Al Nusrah Front in Syria is affiliated with the Iraqi al-Qaida branch. And Hezbollah's involvement has only intensified sectarian violence.

The three-year civil war has claimed some 100,000 lives and forced an estimated 1.9 million Syrians to flee their country, according to the U.N. Why is it taking President Obama so long to take a more assertive policy in Syria?

Manuel: There are no great policy options in Syria. The administration said several times that “stability” in Syria — even if that means a continuing, limited civil war — is more important than a decisive victory over President Bashar al-Assad.  The administration also believes that U.S. military intervention short of using ground troops is unlikely to lead to the creation of a new post-Assad regime that will be friendly to the United States.  Finally, the Obama administration is understandably hesitant to side with the rebel groups, which — in part due to U.S. unwillingness to actively assist moderate Syrian elements for the past two years — have become increasingly radicalized. Al Qaida-allied extremists now make up a growing segment of the rebel movement and some groups are reportedly creating “safe havens” within Syria and Iraq.

Listen to Manuel on public radio KQED Forum about whether U.S. should intervene. 

CISAC's Anja Manuel talks to Al Jazeera America about Syria: 

Have past U.S. intelligence failures made Obama skittish about taking a tougher stance against Syria?

Zegart: Iraq's shadow looms large over Syria. The intelligence community got the crucial WMD estimate wrong before the Iraq war and they absolutely don't want to get it wrong now. People often don't realize just how rare it is to find a smoking gun in intelligence. Information is almost always incomplete, contradictory and murky. Intentions – among governments, rebel groups, individuals – are often not known to the participants themselves and everyone is trying to deceive someone.

What is the intelligence gathering that goes into making the determination that nerve agents were used?

Fingar: The first challenge for the U.S. government is to determine whether and what kind of chemical agents were used. Chain-of-custody issues must be addressed to ensure that samples obtained are what they are claimed to be, and once samples have been obtained, what they are can be established with reasonably high confidence using standard laboratory and pathology techniques.

If it is determined that specific chemical agents were used in a specific place and time, then the next step is to determine who used the agents. Analysts would then search previously collected information to discover what is known about the agents in question, which groups were operating in the area, and whether we might have information germane to the specific incident. Policymakers must be informed about any analytical disagreements if they’re to make informed decisions about what to do in response to the incident.

Pressure on decision-makers to “do something” about Syria may influence their decisions, but it should not influence the judgments of intelligence analysts. If they are suspected of cherry-picking the facts and skewing judgments to fit pre-determined outcomes – they are worse than useless.

See Fingar's comments in The New York Times about the echoes of Iraq.

How do we know the Syrian opposition did not use nerve gas in an effort to provoke military intervention and aid their efforts to topple Assad?

Henriksen: Tracing the precise origin of gas weapons is not an exact forensic science.  It is conceivable that a rebel group staged a "black flag" operation of releasing a deadly gas to provoke a U.S. attack on the Assad regime.  But in this case, both Israeli and Jordanian intelligence reports appear to confirm U.S. identification of Assad as the perpetrator of the chemical attacks. 

If it's confirmed that Syria did use chemical weapons against it own people, is this a violation of the Geneva or Chemical Weapons Conventions?

Weiner:  A chemical weapons attack of the kind that's been described in the media certainly violates the laws of war. Syria, as it happens, is one of only a few countries in the world that is not a party to the Chemical Weapons Convention. Nevertheless, the prohibition on the use of chemical weapons in warfare is a longstanding rule. It is reflected in both the 1907 Hague Convention regulating the conduct of war and the 1925 Protocol for the Prohibition of the Use in War of Asphyxiating, Poisonous or Other Gases, and of Bacteriological Methods of Warfare. (Syria is a party to the 1925 Convention.) The use of a weapon like this also violates the prohibition in the 1977 Geneva Protocols and customary international law on indiscriminate attacks that are incapable of distinguishing between permissible military targets, on the one hand, and the prohibited targeting of civilians and civilian objects, on the other.

If Damascus has violated the conventions, are there non-military actions that can be taken?

Weiner: The illegal use of chemical weapons is a violation of a jus cogens norm, i.e., a duty owed to all states, which means states would have the right to respond to the breach. Such an attack would presumably be a basis for the unilateral imposition of sanctions or severance of relations with Syria. There's an open question under international law whether states not directly injured by Syria's actions could take "countermeasures" that would otherwise be illegal as a way of responding to Syria's illegal action. Under a traditional reading of international law, a violation like this does not give rise to the right by other states to use force against Syria absent an authorization under Chapter VII of the U.N. Charter by the Security Council.

Are there legal means for Washington to bypass the Security Council, knowing that Russia and China would veto any call to action against Syria? 

Weiner: Under the U.N. Charter, a state may use force against another state without Security Council authorization only if it is the victim of an armed attack. Most commentators believe this has been expanded to include the right to use force against an imminent threat of attack. But under the prevailing reading of the U.N. Charter, a mere "threat" to U.S. national security would not provide a justification for the use of force.

But the Obama administration is arguing that Assad's actions pose a direct threat to U.S. national security?

Weiner: Some international lawyers – but not very many – argue that there is a right of humanitarian intervention under international law that would permit states to use force even without Security Council approval to stop widespread atrocities against its own population. But this remains a contested position, and most states, including the United States, have not to date embraced a legal right of humanitarian intervention.

What are some recent precedents in which the U.S. intervened militarily?

Weiner: The situation in Syria is not unlike the one faced in Kosovo in 1999, when a U.S.-led coalition did use force to stop atrocities that the Milosevic regime was committing against Kosovar Albanians. As part of its justification for the use of force, the United States cited the ongoing humanitarian crisis and the growing security threat to the region. What's interesting is that the U.S. was careful to characterize its use of force in Kosovo as "legitimate," rather than "legal."  I am among those observers who think that choice of words was intentional, and that the U.S. during the Kosovo campaign advanced a moral and political justification for a use of force that it recognized was technically unlawful.

How does one know when diplomacy has reached a dead-end and military intervention remains the only course of action?

Henriksen: It has become nearly reflexive in U.S. diplomacy that force is the last resort after painstaking applications of diplomacy. The Obama administration followed that arc dutifully with appeals and hoped that U.N. envoys could persuade Assad to step aside. In retrospect, it seems that U.S. intervention soon after the outbreak of widespread violence in the spring of 2011 would have been a better course of action. Now, Russia, China and Iran have entrenched their support of Damascus. And, importantly, Hezbollah has joined the fight.

Now, with Washington's "red line" crossed by Syria's use of chemical arms, America almost has to strike or lose all credibility in the Middle East and beyond.

Should we be concerned about getting pulled into another long and costly war? Or is there a way to get in, make our point, and get out?

Henriksen: The worry about stepping on a slippery slope into another war in the Middle East is of genuine concern.  Obama's intervention into Libya in early 2011 does provide a model for the use of limited American power. President Bill Clinton's handling of the 77-day air campaign during the Kosovo crisis in early 1999 provides an example of limited interventions. Both these interventions can be analyzed for their pluses and minuses to aid the White House in striking a balance.  But no two conflicts are ever exactly the same.

What is the endgame here?

Henriksen: American interest in the Syrian imbroglio are to check Iran, the most threatening power in the Middle East, and to curtail the conditions lending themselves to spawning further jihadists who will prey on Americans and their allies. At this juncture, it appears that the fragmentation of Syria will become permanent. It's fracturing like that of Yugoslavia in the 1990s and will result in several small states. One or more of these mini-states might possibly align with the United States; others could become Sunni countries with Salafist governments, and the rump state of Assad will stay tight with Iran. The fighting could subside, leaving a cold peace or the tiny countries could continue to destabilize the region. Any efforts that undercut al-Qaida franchises or aspirants are in American interests.