I think Dubya may have dozed off when the difference between Sunni and Shiite Muslims was explained to him. Shiites are generally more radical, fundamentalist and prone to holy war than Sunnis, who tend to be more tolerant. Hussein was the only Sunni ruler in the region. Unlike his son, the elder Bush understood that Saddam was the lesser of the two evils. He therefore refrained from taking him out completely during the first Gulf War.