Syria has had it's own extensive and large-scale WMD programs for longer than Iraq did; I'm a bit baffled as to why people think any of this necessarily has anything remotely to do with Iraq.
UNSCOM supervised the destruction of 500,000 liters of chemical agents alone (a fraction of Saddam's arsenal) in the mid 90s. Find one intelligence report that suggests Syria was ever thought to possess anything close to that. In 2002, the CIA estimated the Syrians possessed several hundred liters.