By Jon Leyne BBC US State Department Correspondent

Listen closely to what the American people are saying about Iraq. It's not nearly as bellicose as the rest of the world fears.

Yes, the public here supports going to war with Iraq. But opinions are not fixed. People have many doubts, which they are only too eager to share with you.

"I think there's a lot of support for what President Bush wants to do," explained one woman to me recently when I visited the east coast city of Baltimore.

"I don't think gung-ho is the right word, that sounds kind of hungry for it, but I think we are resigned that we need to do something."

The headline figures in the opinion polls still show strong support for going to war with Iraq.

• An ABC News/Washington Post poll published last week showed 61% of Americans support attacking Iraq to oust Saddam Hussein.
• That's broadly similar to figures published by Gallup on September 24 - 57% in favour, 38% opposed.
• And another survey released by the Pew Research Centre on September 19 - 64% in favour.

International support matters

But when you ask about willingness to take casualties, support rapidly ebbs.

The Pew survey has only 48% in favour of going into Iraq if it involves significant casualties. That number on its own is not disastrous for President Bush's plans.

"Back in the 90s when we were considering incursions into Bosnia or Kosovo, the prospect of casualties would take support for the use of force into the teens or 20s," explained Andrew Kohut, the director of the Pew Research Centre.

"Casualties are not taken lightly by the American public, but this is still a measure of some potential support for President Bush should he go there," he added.

Many Americans believe that the US needs international support

But with discussions at the United Nations apparently deadlocked, it's the issue of international support that may cause Mr Bush to lose some sleep. He's threatened to go it alone, if he can't bring the UN along.

The American public is far from convinced. In the Pew survey, for example, support for invading Iraq slumps to 38%, with 59% opposed if the United States has to go it alone.

Coalition vital

Time and again that is a message repeated as you speak to people on the streets:

"You have got to have a coalition, it's not good policy to go on your own these days," explained a man I spoke to on the quayside at Baltimore's inner harbour.

Some sceptics have taken to the street to make their views known

He thought that if America went to war without allies, support would be "very mixed."

"I think the mood would be very much like the Vietnam War was received. I think you would have the same sort of backlash.

"I think some people are making some very good cases that we should go a little slower and build a little better coalition and build some support around the world," he said.

President Bush may not care much what the rest of the world thinks.

But his pollsters should be telling him that he needs world support if he is to keep his country united behind him.

And that is a very strong argument for working with the United Nations, and accepting a compromise with the Security Council - however much that appals the hardliners within Mr Bush's own administration.