It's nice to know we're not the only country with reflexive pro-war instincts.

Guardian Unlimited Politics | Special Reports | Support for war surges The outbreak of war has triggered a big surge in support for military action against Iraq among British voters, according to the latest Guardian/ICM tracker poll.

The 15-point swing in public opinion recorded by the ICM survey means that there is now a clear majority, 54%, who back military action, after a sharp rise from 38% just a week ago. The results represent a sudden and widespread shift in public mood in Britain.

Opposition to the war has slumped in the past seven days from 44% to only 30% of the public, the lowest level since the Guardian began tracking public opinion on this issue last August.

An ICM poll for the News of the World over the weekend suggests that this surge in support for military action has been accompanied by a similar revival in Tony Blair's personal ratings.

The big swing in support as British troops go into action demonstrates the highly volatile nature of public opinion on Iraq.

But it must be open to question whether such a level of support can be sustained if there are serious military reverses and a consequent daily diet of harrowing television pictures.

The 30% opposed to the war still represents a substantial minority of the public and is particularly found among the young, Liberal Democrat supporters, and those living in the south-east of England.

The only age range in which opposition to the war is above 50% is the 18- to 24 group.

Nevertheless, the outright opposition of 30% of the adult population is still the highest level of opposition recorded by Gallup at the start of any war since 1950, when 31% said they opposed British troops going to fight in Korea. Fewer than one in four opposed the Falklands war, the 1991 Gulf war or Britain's involvement in Kosovo in 1999.