1. Syria may slip into civil war. This could produce the sort of blood bath that we saw in Lebanon and Iraq that would destabilize the region.
2. Regional capitals will be sucked into the civil war raising the possibility of a larger regional conflagration.
3. Pressure would grow on Western governments to intervene directly. In Iraq, US troops were present to mitigate the worst violence and stem ethnic cleansing and the proliferation of militias and banditry. Syria has no outside force present.
4. Waves of refugees would set out for Turkey and ultimately try to work their way into Europe to find jobs, safety and refugee status. Refugees are a major European fear, as most EU countries already feel overwhelmed by new Muslim immigrants who have caused the rise of Islamaphobia in the West.
5. Moral Leadership. The leadership that Western leaders have already shown in demanding that the Assad regime step down will make it hard for Western leaders not to show the same leadership in protecting vulnerable Syrians and committing troops – perhaps in the context of an international peace-keeping force.
6. If the rebellion takes up arms, the Syrian opposition leadership that is resident in the West will be less likely to have significant influence on the new order established in Syria. Washington and Western capitals will lose their indirect influence over future outcomes.
7. Islamists are more likely to assert leadership over a new Syria if the struggle for power is decided by opposition arms. Islamists have proven to be the more experienced fighters in the region. They may rise to leadership positions in Syria that they do not enjoy today if the end of the Assad regime is brought about by military means.
For these reasons, western leaders will wait to see if sanctions applied to Syria will cause the regime to “collapse” on its own through defections or a coup.