Doesn't 1441 explicitely supersede earlier resolutions ("the Council unanimously adopted resolution 1441 (2002), by which it held Iraq in 'material breach' of its obligations under previous resolutions, and decided to afford it a 'final opportunity to comply' with its disarmament obligations, while setting up an enhanced inspection regime.")?
And by signing up to it, haven't the USA and UK signed up to giving Iraq this final opportunity to comply?
With regard to previous UK/US actions in the No Fly Zone...
Have any of them been overtly aggressive? I don't recall one incident which wasn't 'provoked' by Iraqi AAA or SAM activity. In other words, all have been justified as being defensive actions....
Moreover, most were undertaken when Iraq wasn't co-operating with the Arms Inspection regime, as it seems to be doing now.
That makes such actions entirely different in character to a full-blown invasion of Iraq.