First, from the
War Powers Act(a) Inferences from any law or treaty
Authority to introduce United States Armed Forces into hostilities or into situations wherein involvement in hostilities is clearly indicated by the circumstances shall not be inferred—
(1) from any provision of law (whether or not in effect before November 7, 1973), including any provision contained in any appropriation Act, unless such provision specifically authorizes the introduction of United States Armed Forces into hostilities or into such situations and states that it is intended to constitute specific statutory authorization within the meaning of this chapter; or
(2) from any treaty heretofore or hereafter ratified unless such treaty is implemented by legislation specifically authorizing the introduction of United States Armed Forces into hostilities or into such situations and stating that it is intended to constitute specific statutory authorization within the meaning of this chapter.
The Libya no-fly zone is a
Security Council action under U.N. Charter.
Precedent (long before the WPA passed):
United Nations Security Council Resolution 84United Nations Security Council ResolutionsOn 25 June 1950, the United Nations Security Council unanimously condemned the North Korean invasion of the Republic of Korea, with United Nations Security Council Resolution 82. The USSR, a veto-wielding power, had boycotted the Council meetings since January 1950, protesting that the Republic of China (Taiwan), not the People's Republic of China, held a permanent seat in the UN Security Council.<83> After debating the matter, the Security Council, on 27 June 1950, published Resolution 83 recommending member states yield military assistance to the Republic of Korea. On 27 June President Truman ordered US air and sea forces to help the South Korean régime. On 4 July the Soviet Deputy Foreign Minister accused the US of starting armed intervention on behalf of South Korea.<84>
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Letter from the President regarding the commencement of operations in LibyaUpdated to add a touch of irony:
Iraq war illegal, says Annan:
The United Nations Secretary-General Kofi Annan has told the BBC the US-led invasion of Iraq was an illegal act that contravened the UN charter.
He said the decision to take action in Iraq should have been made by the Security Council, not unilaterally.
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Bush secured an AUMF from Congress, but made false claims in his report in order to launch an illegal attack on Iraq.
Given the War Powers Act section above and the fact that Iraq didn't meet the criteria of an imminent threat, the right course of action would have been to follow the lead of the international community. Millions of lives could have been saved.