It hung even more menacingly over the debate in the British House of Commons Aug. 29 when a 285-272 majority voted against granting the government such authority.
The prevalent idea is that America and Britain were maneuvered into the Iraq War by false intelligence. "Bush lied. People died," Democrats liked to say. Brits denounced Tony Blair's "dodgy dossier."
Yes, both American and British intelligence estimated with high confidence that Saddam Hussein had active weapons of mass destruction. And, yes, after Saddam's downfall coalition forces did not find caches of nuclear or biological weapons, though some evidence of chemical weapons were found.
But intelligence is inevitably an inexact science. And there was strong circumstantial evidence to believe that Saddam was seeking WMDs.
He had, after all, developed and used chemical weapons against his own people in the 1980s. After the Gulf War in 1991, coalition forces found that he had a nuclear weapons program and it was more advanced than had been estimated.
Then between 1991 and 2002, he continually resisted and frustrated international inspection efforts. The obvious conclusion was that he had something to hide.
So back in 2002, no responsible leader could have concluded with certainty that Saddam was not developing WMDs again.
That did not necessarily mean leaders had to support military action. Rational arguments against that were made in the U.S. Congress and the British Parliament.
Military action is always risky but a reasonable person could conclude it was riskier to leave Saddam in power. That doesn't mean that George W. Bush and Tony Blair lied about the intelligence.
How did the idea that we were lied into war become so widely accepted?
One reason is that in America Democrats adopted it as gospel. Many of them regarded Bush's election as illegitimate, even though every newspaper recount still showed him ahead, barely, in Florida.
Democrats also deeply resented Bush's insistence on a vote on the Iraq War resolution in October 2002, a month before the midterm election and at a time when support for military action was about 70 percent in polls.