John Curtice: Public patience is wearing thin - and may run out completely

Tony Blair has always been struggling to bring the country behind him on Iraq. Even at the height of the war, with all the pressure to "back our boys", only about three in five reckoned the decision to invade was justified.

Twelve months later, it looks as though public support for keeping British troops in Iraq is in danger of evaporating.

In an exclusive poll conducted for The Independent by NOP, just 28 per cent said that British troops should stay in Iraq after sovereignty is handed to an Iraqi government at the end of June. No less than 55 per cent say that British troops should be pulled out by then, including some 16 per cent who would like troops to be withdrawn immediately.

This result is different from that found by other recent polls. ICM reported last month that 51 per cent believed British and American troops should stay in Iraq for as long as necessary. Now it seems that little more than a quarter take that view. Our polling was conducted as the first allegations of the abuse of Iraqi prisoners by American and British soldiers hit the headlines. So it could be the first evidence that not only have doubts about the original decision to go to war grown in recent weeks - just over 40 per cent now consider it was justified - but that the recent allegations have also undermined public support for keeping our troops there.

This may, however, be too simple an explanation. The 16 per cent who said in our poll that they were in favour of the immediate withdrawal of troops is less than the 27 per cent who took that view in ICM's poll. And if people were simply reacting to the horror of the images and allegations of the past 10 days, we might have expected more to say they wanted our troops to leave immediately.

Instead, our poll may point to a potentially far more persistent problem than short-term adverse headlines. Rather, it suggests that once sovereignty has been handed back to Iraq on 30 June the public may begin to ask why British troops are still there. For in our poll, unlike ICM, NOP explicitly reminded people that power is to be handed back to the Iraqi people next month. It seems that for many people this appears to be the logical moment for our troops to come home too.

So far, the British and US governments have been hoping that by keeping to the deadline of 30 June for handing back power, they will show that the security situation is under control and that the peace is being won. This, they hope, will quell both domestic and international criticism of their handling of the postwar situation. But it seems they have ignored the prospect that if the Iraqis really can now run their country, then the public will begin to wonder why "our boys" cannot be welcomed home.

John Curtice is professor of politics at Strathclyde University