http://www.timesonline.co.uk/printFriendly/0,,1-524-1648758-524,00.htmlThe Goal
5. Our objective should be a stable and law-abiding Iraq, within present borders, co-operating with the international community, no longer posing a threat to its neighbours or to international security, and abiding by its international obligations on WMD. It seems unlikely that this could be achieved while the current Iraqi regime remains in power.
US military planning unambiguously takes as its objective the removal of Saddam Hussein's regime, followed by elimination if Iraqi WMD. It is however, by no means certain, in the view of UK officials, that one would necessarily follow from the other. Even if regime change is a necessary condition for controlling Iraqi WMD, it is certainly not a sufficient one.
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Justification
11. US views of international law vary from that of the UK and the international community.
Regime change per se is not a proper basis for military action under international law. But regime change could result from action that is otherwise lawful. We would regard the use of force against Iraq, or any other state, as
lawful if exercised in the right of individual or collective self-defence, if carried out to avert an overwhelming humanitarian catastrophe, or authorised by the UN Security Council. A detailed consideration of the legal issues, prepared earlier this year, is at Annex A. The legal position would depend on the precise circumstances at the time. Legal bases for an invasion of Iraq are in principle conceivable in both the first two instances but would be difficult to establish because of, for example, the tests of immediacy and proportionality. Further legal advice would be needed on this point.