RTFI ignores UN resolution 688, which is generally considered to provide the "legal" basis for the operation of the no-fly zones. This was followed by the setting-up of the North Zone following a pretty savage attack on the Kurds, from Iraqi helicopter gun-ships, followed by the Southern Zone a year later following an equally savage attack against the Shi'ite Muslims in the South.
Because this Resolution did not specifically detail the scope and operation of these zones, pro-Iraqi sympathisers tend to disagree about their "legality".
Certainly there appears to be greater "moral" than "legal" grounds, as mentioned in a recent HofC committee as reported at:
http://www.fas.org/news/iraq/2000/07/45306.htm#a8