Former US terrorism czar Richard Clarke's allegations - headlined on America's morning news - are a blow to a White House which intends to portray the president in this election year as a tireless fighter against terrorists.
The White House has mounted an aggressive defence
The reality, according to Mr Clarke, is that the Bush Administration was so obsessed with Iraq that even after the 11 September attacks, key figures were looking for excuses to bomb Baghdad rather than Afghanistan - where al-Qaeda was based.
We are all aware of the certainty US Defence Secretary Donald Rumsfeld exuded before the war on the subject of Iraq.
And according to Mr Clarke, that unshakeable view of the dangers posed by Iraq allowed America's defence secretary to make some extraordinary efforts - in the days after the 11 September attacks - to bomb Saddam Hussein rather than al-Qaeda.
Mr Clarke said: "When we talked about bombing the al-Qaeda infrastructure in Afghanistan, Donald Rumsfeld said there were no good targets in Afghanistan: Let's bomb Iraq."
Mr Clarke countered that Iraq had nothing to do with the attacks.
"That didn't seem to make much difference" to Mr Rumsfeld, he added.
The Iraq obsession, according to Mr Clarke, was not just lodged in the mind of the defence secretary - the president himself had caught the bug.
The White House is rattled.
Rattled because these are grave allegations to make in election year and rattled because the man making them is a serious player: an anti-terrorism advisor to four successive presidents from Ronald Reagan through George W Bush.
National Security Adviser Condoleezza Rice took to the airwaves to rubbish the work Mr Clarke had done for the President.
"The president needed more. He needed a strategy that would eliminate al-Qaeda. He needed a strategy that was going to get serious about real military options against al-Qaeda," Dr Rice said.
She added, "I didn't have that strategy on 24 June from Mr Clarke."
There is something rather odd about Mr Clarke's timing. He has chosen to make these allegations in a spectacular fashion to sell a book and he's done it during an election campaign.
White house spokesman Dan Bartlett asks us to take these facts into account.
"If he had such grave concerns about the actions that we took over a year ago in Iraq and the consequences it would have in the war on terror, why is it only now that he is raising these issues in the middle of a political campaign?" he asks.
Nonetheless, the Clarke case is now in the court of public opinion, and if Americans choose to believe it, the president will be gravely damaged.