The Bush administration at last may have to explain why it led the nation into the war with Iraq.

The decision to launch the invasion of Iraq has led America into a quagmire that more and more resembles our involvement in Vietnam 40 years ago.

In a Veterans Day address in Tobyhanna, Pa., on Friday, President George W. Bush, obviously feeling the heat from growing opposition to the war and his low standing in public opinion polls, lashed out at Democratic critics, saying more than 100 congressional Democrats voted to support the war against Saddam Hussein.

The administration's new defensiveness surfaced after Senate Democrats forced the Senate Intelligence Committee to move on to the second phase of its inquiry into pre-war intelligence and answer the question: Did the administration manipulate the intelligence process in order to come up with a justification for invasion?

Sen. Pat Roberts, R-Kans., the committee chairman, has been dragging his feet, to put it mildly, about undertaking this inquiry. The Democrats forced the issue by holding an extraordinary closed-door session last week and compelling Republican members to agree to push ahead on the promised probe.

The Democrats want to mine the statements of administration officials to determine whether intelligence was distorted or exaggerated in their public statements in the prelude to the war.

A report on the first phase of the investigation -- which was issued in July 2004 -- said the CIA's prewar assessments of Iraq's arsenal of weapons of mass destruction were wrong.

Roberts said that the intelligence community told the president, Congress and the public that Saddam Hussein had stockpiles of chemical and biological weapons and that Iraq would have nuclear weapons in a decade if a buildup continued.

Sen. Jay Rockefeller, D-W.Va., the committee co-chair, said when the report was issued: "We in Congress would not have authorized that war with 75 votes if we knew what we know now."

Sen. Carl Levin, D-Mich., the top Democrat on the Senate Armed Services Committee, says he has evidence that the administration's use of prewar intelligence was misleading and deceptive.

Sen. Harry Reid, D-Nev., the Democratic leader in the Senate, says the second phase of the Intelligence Committee's investigation should come up with answers to three key questions: How did the Bush administration build its flawed case for war? How did the Bush administration sell its case for war? How did the Bush administration coordinate and carry out its strategy to squelch its critics?

Rockefeller is holding out the possibility of issuing subpoenas to policymakers and speechwriters as part of the inquiry. That's a big task, considering the administration's intense sales campaign and the torrent of statements by Bush, Vice President Dick Cheney and then-national security adviser Condoleezza Rice in the months before the invasion of Iraq.

Of special interest in the committee's investigation will be Cheney's repeated visits to CIA headquarters amid speculation that he was applying subtle pressure on agency analysts to adopt the administration's views.

CIA director George Tenet, who certainly knew what Bush wanted to hear, ended up telling the president that it was a "slam dunk" that Saddam had the lethal weapons. There are many marquee statements in the administration's marketing campaign to drum up support for the attack.

For example, in September 2002 Rice said on CNN: "We do know that he (Saddam Hussein) is actively pursuing a nuclear weapon. The problem here is that there will always be some uncertainty about how quickly he can acquire nuclear weapons. But we don't want the smoking gun to be a mushroom cloud."

Cheney insisted that Iraq was embarked on a nuclear weapons program and that "we know where they are."

At one point after the invasion, Bush exclaimed to reporters: "We have found the weapons."

We have yet to hear any apologies for any of those tall tales.

If it turns out that Bush and his advisers had no compelling reasons to believe their rhetoric, then the president will have to explain what motivated him to start the costly war that has taken more than 2,000 American lives and killed many thousands of Iraqis.

The administration has managed to avoid explaining the real "whys" for the war. But its ever-changing rationales are not lost on the American people who now must know that the reasons marketed to invade Iraq were simply false. We need a moment of truth.

(Helen Thomas can be reached at the e-mail address hthomas@hearstdc.com).

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