The fact that Saddam had WMDs was somewhat secondary to the liberation of Iraq, but I have never doubted that he had some. Certainly he wanted to give the impression - afraid as he was of Iran and Israel - that he was in possession of large stockpiles of WMDs and must have kept some stock of them for a rainy day. It was enough for Saddam to gas a few Kurds or Shia now and then to keep alive his image of ruthlessness and inspire awe in his enemies.
Check the excellent IRIS blog on the strong new evidence emerging on Saddam's WMDs:
Explosives and poison gas that could have killed as many as 20,000 people and decapitated his government came from Syria, Jordan's King Abdullah told the San Francisco Chronicle last Saturday. An al Qaida cell associated with Abu Musab al Zarqawi, a Jordanian national thought to be masterminding al Qaida operations in Iraq, smuggled three cars containing 17.5 tons of explosives and a deadly chemical agent of an undisclosed type into Jordan early in April ...
Much more at the link.