Resilience of the Syrian regime

I have raised this point before about the lousy Syrian regime: that it has surprisingly remained largely resilient.  There have been no defections whatsoever in the diplomatic corps.  There are no defections in the government bureaucracy either.  The military defections, remain, despite wild exaggerations in the propaganda of Ikhwan, remain limited. What is my explanation? Not that the regime is popular but that those people (many of whom are opposed to the regime, I know) have thus far reached the conclusion that the regime is not collapsing any time soon.  People defect (you saw it in Libya) only when they calculate that the regime won't be able to salvage itself.