At a press conference to spell out the reasons for the military campaign, he released a dossier on human rights violations by Iraq, describing the systematic use of torture by Saddam throughout his state against people who opposed him.
"It is important to remember what kind of man it is that our bomber pilots are flying against, and what kind of regime it is that Britain is fighting," he said.
Some of the information came from Iraqi defectors and from secret intelligence sources, and the dossier included reports by Amnesty International and United Nations special rapporteur Max van der Stoel.
One example of Iraqi brutality quoted by Mr Cook was that Saddam's son, Uday, had ordered that the entire Iraqi football team should have the soles of their feet beaten for failing to qualify for the World Cup.
Staff developing weapons of mass destruction had to accept that they would incur the death penalty if they left the programme without authority, he added.
Mr Cook spoke of the use of genocide against minorities within Iraq. One campaign against the Kurds had led to between 70,000 and 150,000 deaths. Orders for that campaign provided for the indiscriminate execution of all males between the ages of 15 and 70.
Frequent TV pictures of Saddam had made it easy for us to become familiar with him, said Mr Cook. "In the case of Saddam, familiarity must not be allowed to breed indifference."
Mr Cook outlined the continuing policy of containment of Saddam. The three aims of this were: to mount a credible threat against any attempt to re-develop weapons of mass destruction; to maintain vigilance and effective monitoring; and to seek to isolate Saddam's regime while wherever possible giving support to those who oppose him.
Earlier today, the Ministry of Defence issued another dossier recording the brutality of Saddam, his family and the regime.
It described Saddam as a "cold-blooded murderer", who shot a minister during the Iran-Iraq war for advocating peace in a Cabinet meeting; and was widely thought to be behind the death of his wife's brother in a helicopter "accident".Reuse content