A leading supporter of the Iraq war has accused President George W Bush of trying to hoodwink Americans into believing the campaign would be "a day at the beach".

Senator John McCain, a Republican who is expected to run for the presidency in two years' time, focused his anger on statements from Mr Bush, Donald Rumsfeld, the defence secretary, and the vice-president, Dick Cheney, since the overthrow of Saddam Hussein three years ago.

Americans, he said, "were led to believe this could be some kind of day at the beach, which many of us fully understood from the beginning would be a very, very difficult undertaking."

Mr McCain then listed the most controversial sound-bites offered by the men in charge of the Iraq campaign since then: 'Stuff happens', 'mission accomplished', 'last throes', 'a few dead-enders'.

"I'm just more familiar with those statements than anyone else because it grieves me so much that we had not told the American people how tough and difficult this task would be," he said.

The war in Iraq has killed 2,613 American and 115 British troops, as well as more than 30,000 Iraqis. The lowest estimates suggest that the Iraq and Afghanistan campaigns have cost American taxpayers at least $400 billion (£210 billion) but some experts say the real figure could be close to $1 trillion (£528 billion).

His words were echoed by another senior Republican senator, Lindsey Graham, who said: "I think we undersold how hard the war would be. I think we oversold how easy it would be to create democracy. I think we missed by a mile how much it would cost to rebuild Iraq."

Such reflections have become commonplace. The conservative commentator George Will has accused the Bush administration of destroying Middle Eastern stability. That caused the White House to issue a 2,500-word attack on Mr Will's views, concluding that his approach "would eventually lead to death and destruction on a scale that is almost unimaginable".

Yet opponents of the policy in Iraq lack unity. Senator McCain and other presidential hopefuls such as Senator Hillary Clinton are extremely careful about what they say, largely because they accept Mr Bush's argument that withdrawal would make the situation worse and make Iraq a haven for terrorist groups.

Mr McCain said withdrawal would result in "chaos. . . that would have direct implications for our national security".

American foreign policy experts on both sides of the argument accept that the September 11 atrocities happened in part because Afghanistan had become a haven for al-Qa'eda. Mr Bush rammed the point home this week, warning terrorists would "follow" America home if it left Iraq.

Some Democrats have called for an early exit, but that remains highly controversial. Polls show Americans have concluded that Iraq has emboldened their terrorist foes and that the Bush administration has mishandled the war. They are split on the need for a pull-out.

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