Full-on account from The New Republic about the Deceptions:

From late August 2002 to mid-March of this year, the Bush administration made its case for war by focusing on the threat posed to the United States by Saddam Hussein's nuclear, chemical, and biological weapons and by his purported links to the Al Qaeda terrorist network. Officials conjured up images of Iraqi mushroom clouds over U.S. cities and of Saddam transferring to Osama bin Laden chemical and biological weapons that could be used to create new and more lethal September elevenths. In Nashville on August 26, 2002, Vice President Dick Cheney warned of a Saddam "armed with an arsenal of these weapons of terror" who could "directly threaten America's friends throughout the region and subject the United States or any other nation to nuclear blackmail." In Washington on September 26, Secretary of Defense Donald Rumsfeld claimed he had "bulletproof" evidence of ties between Saddam and Al Qaeda. And, in Cincinnati on October 7, President George W. Bush warned, "The Iraqi dictator must not be permitted to threaten America and the world with horrible poisons and diseases and gases and atomic weapons." Citing Saddam's association with Al Qaeda, the president added that this "alliance with terrorists could allow the Iraqi regime to attack America without leaving any fingerprints."

Yet there was no consensus within the American intelligence community that Saddam represented such a grave and imminent threat. Rather, interviews with current and former intelligence officials and other experts reveal that the Bush administration culled from U.S. intelligence those assessments that supported its position and omitted those that did not. The administration ignored, and even suppressed, disagreement within the intelligence agencies and pressured the CIA to reaffirm its preferred version of the Iraqi threat. Similarly, it stonewalled, and sought to discredit, international weapons inspectors when their findings threatened to undermine the case for war.