As Stratfor has noted, the ideal outcome for the West in Syria would be a slow and negotiated handover of power that guarantees the control and containment of the chemical stockpiles. Nevertheless, the West already has contingencies in place in case a sudden security lapse leaves these weapons unaccounted for.
Securing Syria's chemical weapons would require the projection of air or ground forces into the country, necessitating a comprehensive suppression of enemy air defenses, or SEAD, campaign. The bulk of Syria's air defense systems are located in western Syria, where the majority of the regime's alleged chemical weapons stockpiles are likewise located — Palmyra is the lone exception. The need to suppress enemy air defenses would abate only if the Syrian air defense network degrades through fighting on the ground.
The severity of Syria's chemical weapons situation would determine how intervening forces would secure the weapons. If the situation requires an immediate and limited response, airstrikes or cruise missile strikes would be the preferred options. Israel conducted just such an operation against a suspected nuclear site in eastern Syria in 2007. The problem with these kinds of operations is that they do not guarantee the complete destruction of the hazardous material associated with the chemical weapons. Militants could obtain any material left intact after the strike. Moreover, an airstrike or missile strike could release some of the hazardous material into the area.
But a far more comprehensive response would be required if multiple chemical weapons manufacturing or storage facilities are abandoned as security degrades in Syria. Intervening forces would need more time to gather the requisite forces to secure all sites. In this scenario, numerous detachments of special operations forces would need to be inserted into Syria. Such a deployment likely would be preceded by the seizure of an airfield to act as a temporary base for the operations. If the decision were made to expand the mission to include multiple suspected chemical weapons sites, then additional personnel would be deployed.
A Last Resort
Large, comprehensive intervention campaigns would fully enmesh the intervening countries in Syrian affairs. Countries willing to participate in such campaigns would have to consider the political implications — casualties and collateral damage, for example — of military intervention. Moreover the potential for mission creep would be high, and agreeing upon an exit strategy would be difficult, especially if it were decided that all chemical weapons facilities needed to be secured. For example, the U.S. military reportedly estimates that it would require 75,000 troops to secure the entire network of Syrian chemical weapons. An expanded mission involving this many troops would fully implicate the United States in another major war in the Middle East.
For these reasons, the United States and its allies would be reluctant to carry out a large operation to secure loose Syrian chemical weapons and likely would do so only as a last resort. The United States and Israel already use a substantial amount of intelligence assets to determine if or when they would intervene.
In any case, intervention would be a precarious task fraught with geopolitical risk and consequences. Potential intervening actors would prefer to work with rebel forces on the ground to secure the sites. As Syria's security situation deteriorates further and the rebels make additional gains, the United States and other countries likely will accelerate their cooperation efforts with the rebels to achieve these goals.