The core of Dubya's justification for armed action on Iraq in particular (as opposed to numerous other states which also sponsor terrorism of some sort), from his speech:

The regime of Saddam Hussein cultivated ties to terror while it built weapons of mass destruction. It used those weapons in acts of mass murder and refused to account for them when confronted by the world.

The Security Council was right to be alarmed. The Security Council was right to demand that Iraq destroy its illegal weapons and prove that it had done so.

The Security Council was right to vow serious consequences if Iraq refused to comply. And because there were consequences, because a coalition of nations acted to defend the peace and the credibility of the United Nations, Iraq is free.

What did it mean that Saddam Hussein's regime "failed to comply"? They did supply hundreds of pages of documentation -- including documentation on the risible drone program and the al-Samood 2 missiles -- but claiming that preexisting WMD programs had been shut down, and the products destroyed. Before the war, Dubya and his crew claimed over and over that they were lying. And Dubya's new speech only makes any sense at all as a repetition of those claims -- if Saddam destroyed his weapons and accurately said so, what was the problem?

So, ummm... where are the weapons?

More: And, oh by the way, why was Colin Powell claiming, on Feb. 24, 2001, according to this official State department transcript, that:

[Saddam Hussein] has not developed any significant capability with respect to weapons of mass destruction. He is unable to project conventional power against his neighbors.

(He was defending sanctions at the time, attributing this success to that policy).

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