The claim in question: President Bush told the United Nations General Assembly in 2002 that "Iraq has made several attempts to buy high-strength aluminum tubes used to enrich uranium for a nuclear weapon." Paul Morse/White House

The ferocious debate over intelligence failures in the lead up to the Iraq war centers on whether U.S. President George W. Bush and his senior aides exaggerated, distorted, or unduly influenced the judgments of the intelligence community. In particular, critics point to the President’s 2003 State of the Union speech, in which he made reference to Iraq’s alleged efforts to acquire uranium yellowcake from Africa—a claim that the CIA dispatched U.S. diplomat Joseph Wilson to investigate. Given the imbroglio that has resulted, it’s not surprising that the African uranium claim has become emblematic of a larger intelligence debacle. But all the ballyhoo surrounding Wilson and his wife, Valerie Plame, has obscured a much clearer case of exaggeration in the run up to the war in Iraq: aluminum tubes.

The Bush administration’s most blatant misrepresentation of intelligence was its claim that Iraq’s attempts at purchasing thousands of high-strength aluminum tubes was part of an effort to build nuclear centrifuges to produce highly enriched uranium for weapons. In the fall of 2002, the aluminum tube claim was the top administration talking point as President Bush made his case for war to the U.S. Congress and the United Nations. Yellowcake wasn’t really in the picture until well after Congress voted to authorize the use of force. Iraq already possessed considerable amounts of uranium and other materials required to make nuclear bombs, so an additional purchase from Africa wouldn’t make much of a difference. Without the aluminum tubes, however, Iraq could not enrich that uranium to weapons-grade fissile material.

The administration failed to disclose key dissents on this issue from U.S. government officials with great expertise on uranium enrichment programs. Both State Department intelligence analysts and Department of Energy centrifuge experts believed the aluminum tubes were likely intended for Iraq’s conventional artillery rocket program, not for nuclear centrifuges. The tube specifications, they argued, deviated significantly from those required for centrifuge rotors. And if the tubes were for centrifuge enrichment, why didn’t the Iraqis make a more robust effort to conceal their purchase?

These serious and well-informed doubts were ignored. On September 8, 2002, Michael R. Gordon and Judith Miller reported in the New York Times that, “[t]he diameter, thickness and other technical specifications of the aluminum tubes had persuaded American intelligence experts that they were meant for Iraq’s nuclear program.” That same day, senior Administration officials fanned out on the Sunday talk shows to reinforce the report. On CNN’s Late Edition with Wolf Blitzer, then National Security Advisor Condoleezza Rice told viewers that the tubes “are only really suited for nuclear weapons programs, centrifuge programs.” When the president addressed the United Nations General Assembly a few days later, he cited the attempted tube purchases as clear evidence that Iraq was reconstituting its nuclear program. He and other senior Administration officials continued to cite the aluminum tubes at every opportunity before Operation Iraqi Freedom commenced.

An Iraq equipped (or about to be equipped) with nuclear weapons was the ultimate trump card needed to convince the American public that a preventive war was necessary. Pointing to Iraq’s chemical and biological weapons would only partly do the trick. The United States had provided support to Iraq during its war with Iran in the 1980s, when it both possessed and used chemical weapons. After the 1991 Gulf War, Washington had successfully contained Saddam and his chemical and biological weapons. But with nuclear weapons, Iraq could defy the United States, break out of the U.N. sanctions regime, and bully its Persian Gulf neighbors. The administration’s repeated references to contacts between Saddam’s regime and al Qaeda leaders became particularly foreboding in this nuclear context: How could America tolerate the prospect of Saddam transferring nuclear weapons or know how to Osama bin Laden?

Hussein’s supposed efforts at acquiring nuclear weapons capability provided the ultimate rationale for war. As the U.S. Senate Select Committee on Intelligence continues the second phase of its investigation into prewar intelligence, it must assess how and why the trumped-up intelligence on aluminum tubes came to form the heart of President Bush’s campaign for war.