It is whispered about at the margins of meetings and discussed in Washington parties where rumour is passed around with the wine and canapés. It even appears, fleetingly, to be fact.

“The day nobody died from violence in Iraq” is a date that has been much anticipated in the White House — where President Bush is desperate to hail the success of his surge of 30,000 troops this year. But no one can quite say when this event, longed for by most, if not all, people on the street corners of Baghdad, occurred.

“It was some time this week, wasn’t it?” says a senior military source. “Or maybe last week.” Another diplomatic official confidently asserted that there were “at least two such days this month”. When, exactly? “Not sure,” he replied.

Such foggy vagueness may be concealing a truly significant transformation on the ground in Iraq.

There have certainly been several days in the past month when no US or British soldiers were killed.

During a five-day stretch between October 19 and 23, there were no deaths among coalition forces. Although three US servicemen died from “non-hostile causes”, this was the longest period without combat deaths for nearly four years. And, between October 27 and 29, there were three more days without coalition deaths.

Such statistics do not take account of deaths among the Iraqi security forces or civilians. But Iraqis, too, have had days when no one in their ranks has died. On October 13, for instance, neither the coalition nor the Iraqi military suffered any deaths. But one Iraqi policeman was killed, along with four reported civilian deaths in Baghdad.

Two days later, there were no deaths among the coalition but six among the Iraqi security forces.

October 19 was a death-free day for both coalition and Iraqi security forces, but 12 civilians were killed.

The civilian death toll was lower on October 23 — when four were killed — but they were joined in the mortuaries by two Iraqi policemen. On October 30 this week, the Iraqi Ministry of Interior reported that there were no civilian deaths at all in Baghdad, but three US troops and four Iraqi policemen were killed.

It is beyond dispute, though, that the tide of violence in Iraq has been stemmed. In a speech to troops in Fort Jackson in South Carolina yesterday, Mr Bush trumpeted the growing co-operation between Sunni and Shia Muslims in fighting al-Qaeda, the dramatic turnaround of Anbar province, and the decline in US military deaths, which he said were at their “lowest for 19 months”.

He said: “The enemy remain determined but what they have learnt about the United States of America is that we are more determined.” In a significantly more upbeat speech than those he delivered earlier this year, Mr Bush declared that this was a “fight we will win”, adding: “Victory starts here.”

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