You can sometimes tell when a political conversation is at a turning point because the rhetoric goes nuclear. With respect to the Iraq war, that is what is beginning to happen in America.

Last week saw Dick Durbin, a leading Democratic senator, compare an account of detainee treatment at Guantanamo Bay with prisoner abuse in totalitarian regimes. It also saw Karl Rove, the president’s most powerful political aide, essentially call all “liberals” a danger to their country for their response to 9/11 and the Iraq war.

Chuck Hagel, a leading Republican senator, called the White House “completely disconnected from reality. It’s like they’re just making it up as they go along”. The internet blogs and the op-eds were full of similarly calm discourse.

It’s not that the Bush administration policy is likely to change any time soon. It’s that the American people have reached a point of no return with the president and his constant and unpersuasive assertions that everything is just peachy in Mesopotamia.

A poll that showed 60% of Americans want to start removing troops from Iraq merely confirmed the obvious: Bush’s war policy can no longer be sustained by the kind of “trust us” condescension that he has previously employed.

The doubts have increased markedly since America woke up to the secret Downing Street memos that shatter illusions about the build-up to war. The memos — first revealed in The Sunday Times by Michael Smith on May 1 — have since stormed through American websites and made headlines in the mainstream US media.

Last weekend the Associated Press agency moved a special package of six articles on the memos to its media subscribers throughout America.

The memos reveal that Tony Blair agreed to support President George W Bush’s plans for regime change as early as April 2002 — a year before the war started. They also show that the head of MI6 reported back from America to Blair that the “intelligence and facts were being fixed around the policy”.

They describe American efforts to find a cause for war as “frankly unconvincing”. And, perhaps most damningly in US eyes, the memos reveal that little effort was made to plan for the aftermath of invasion — which is still costing hundreds of American and Iraqi lives — despite warnings that it could be messy.

“A post-war occupation of Iraq could lead to a protracted and costly nation-building exercise,” warned one memo in July 2002. “The US military plans are virtually silent on this point.”

THE debate on the war has polarised yet again — and the poles are further apart than ever. On the one extreme are those in the Bush camp who argue that the war is all but over and that we have already won. On the other are those who opposed the war in the first place and seem to take a perverse pleasure in every discouraging news report. In between are various shades of hope and disappointment, despair and grim resolution.

In all of these positions there is a new intensity. That intensity suggests that the long period of acquiescence in a policy barely explained and riddled with inconsistency is coming to a close. Some kind of tipping point is approaching — either for or against the entire venture.

The Bush boosters engage in several arguments. The first is that the mainstream media have deliberately ignored the good news from the country. Much of Iraq, they argue, is peaceful; the economy, after a nosedive, is recovering; the elections proved that the Iraqis want democracy; there are signs that the Sunni minority is beginning to accept a bigger role in the constitutional and political process.

Explore UK News

• Crime News

• Education News

• Health News

• Scotland News

Times Recommends

• Oh no, Mr Darling: you have failed
• BBC survives dogfight over Kennel Club expose
• Where the Rosetta belongs can’t be set in stone