Well, If Clinton is serious, she should be sitting in Assad's office armed with a comprehensive and consistent US strategy for approaching the Middle East in the current era; as well as a focused plan for dealing with Arab Spring as it continues to unfold across the region. She should also have a comprehensive package of carrots and sticks to employ in the course of her conversation. She should refrain from making shoulder fired verbal assaults at Assad in the media and keep statements to a sophisticated planned message theme that addresses this (so far as I know, non-existent) overall US strategy and scheme.

On Rex's point that there may be some fence sitters who could be swayed by sanctions, then I suggest that only go after those fence sitters in that fashion if one can narrowly tailor a sanction, like a laser or GPS guided munition, to hit them. That may be in their personal bank accounts overseas, perhaps. Freezing Swiss and UAE accounts is unlikely to hurt the average Syrian much. Something along those lines.

And as always, whatever we do to Syria we need to be equally prepared to do in Saudi Arabia when that time comes (and it will come) as well.