Washington police are bracing themselves this morning for what could be the biggest weekend of protest in the US since the Seattle riots of 1999. With thousands of demonstrators expected, commuters have been urged to stay off the roads to prevent chaos.

The event is timed to coincide with the annual meetings of the World Bank and International Monetary Fund, but the demands on the placards will cover matters way beyond world capitalism - with the impending attack on Iraq probably top of the agenda.

As ever, the protesters will be ignored if they are peaceful, and condemned - but noticed - if they are not. But they will gather with a growing sense that the anti-war forces in the US have, not the wind behind them exactly, but at least the first puffs of a breeze.

Those implacably opposed to the war range from the far left to one congressman normally regarded as an extreme rightwinger. This week they at last acquired a semblance of leadership when the two most important Democrats, Al Gore - increasingly likely to be the presidential candidate again in 2004 - and the Senate majority leader, Tom Daschle, stopped trying to change the subject away from Iraq and hit back at the president.

In one of the most electrifying speeches the current Senate has heard, Mr Daschle, almost in tears, condemned as "outrageous" White House attempts to equate criticism with lack of patriotism.

He said he had never seen the words "Democrat" or "Republican" on a soldier's grave.

"We ought not politicize this war. We ought not politicize the rhetoric about war and life and death," he said.

The president failed to offer the apology Mr Daschle wanted, but changed his tone. "Democrats and Republicans," he said inclusively and pointedly, "refuse to live in fear."

The White House is negotiating with congressional leaders on the wording of the resolution they are expected to pass authorizing military action in Iraq. The negotiations are "civil", the president said, which may not be the whole truth.

Part of the subtext of the Daschle attack was that the administration is spinning the arguments out so the vote is held closer to the midterm elections on November 5.

Both houses of Congress should pass authorizing resolutions by large majorities, with Mr Daschle and other Democrat leaders in reluctant acquiescence. But there will be a revolt, perhaps a substantial one.

This reflects a very different public mood from a year ago when only one lone Congresswoman, Barbara Lee of California, rejected the president's demand to act on Afghanistan.

There are also memories of the most infamous of these votes, in 1964, when just two senators voted against giving Lyndon Johnson authority to go to war in Vietnam.

The Senate figures may depend on the final judgment of a few influential doubters, like the respected Republican foreign affairs specialist Chuck Hagel. In the House of Representatives, where all the members face re-election, decision-making is complicated by imminent political concerns.

But David Bonior, a former Democratic whip, insisted that up to 100 of the House's 212 Democrats could vote against, along with "a handful" of Republicans.

Mr Bonior is visiting Baghdad with an anti-war colleague, Jim McDermott. They are politically fireproof: Mr Bonior is not running again, and Mr McDermott has a safe seat in liberal Seattle.

But they and other hardcore members of the awkward squad report a surprising amount of support for their stand even in less promising parts of the country. Marcy Kaptur, a Democrat congresswoman from Ohio, said she was buoyed up by the response of voters.

"I had a big party meeting in Toledo this week and, just listening to the people, you could tell the country isn't where the president is. They're stunned at the thought of war," she said. "I left Washington where the place is hunkered down for war. Back there they're concerned about the Oktoberfest, and the baseball and the football.

"I've had people coming up to me and questioning the president's balance and judgment. If there's an imminent threat, that's different, but they don't see it. "

Her views are echoed by a more improbable figure: Ron Paul, an off-message anti-government-interference Republican from Texas who rejects assisted health care as well as aggressive wars.

Mr Paul, who came third in the 1988 presidential election on the Libertarian ticket, brandished 200 papers which he said were the day's e-mail intake. "There's about 10 in there which say I'm a jerk," he said. "Most are very supportive."

He says that pre-emptive strikes are unconstitutional, since the president only has the right to respond to imminent threats, adding: "I disagree that there is a threat to the US from someone as small and ill-equipped as Saddam Hussein."

Ron Paul makes an unlikely bedfellow with the protesters due on the streets today, but this is a strange alliance. About 70 items of street art - decorated donkeys and elephants that have adorned Washington pavements this summer - have been moved for fear of vandalism.

They have found sanctuary in the grounds of a university. The idea that a student campus should be considered a safe haven from anti-war activists is just one more sign that this is not a re-run of the 1960s.

The lesson of Vietnam

The words "Gulf of Tonkin" have echoed round Washington again this week as old-timers remember how war panic can produce bad law. In August 1964, just two senators - Wayne Morse of Oregon and Ernest Gruening of Alaska - held out against a tidal wave of indignation.

President Lyndon Johnson got Congress to authorize"all necessary measures" after two North Vietnamese patrol boats reportedly launched unprovoked attacks on US ships. This became the legal basis for the subsequent war.

It is widely accepted now that the first ship attacked, the USS Maddox, was spying, and that the second attack did not happen.

Mr Gruening said: "This resolution is a further authorization for escalation unlimited. I am opposed to sacrificing a single American boy in this venture."

Mr Morse said: "I believe this resolution to be a historic mistake."

Nine years later, the War Powers Resolution was passed: now a president can take military action immediately, but he must go to Congress within 60 to 90 days for permission to continue the engagement.

© Guardian Newspapers Limited 2002

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