[FirstPrinciple]

Saddam had to pretend that he had WMD in order to stay in power. If word got out that he didn't, Iranians and the Kurds would have taken him down right away. It was his way to keep himself in power.

[steve-b]

Saddam had to pretend that he had WMD in order to stay in power.

Also, his experts had to tell Saddam that they could have WMD ready Real Soon Now (whether they could or not) in order to stay alive.