We found out from Saddam after he was captured that his strategy was to make everyone - even his own people - believe he could and would use WMD. He went to great lengths to do so.
He thought this would keep us from attacking him.
http://www.nytimes.com/interactive/2014/12/03/world/middleeast/chemical-weapons-iraq-pentagon-secrets.html
Saddam’s bravado was also aimed at Iran during their endless wars.