Editor’s note: This column has been updated to reflect Tuesday’s Senate vote

WASHINGTON — Within three weeks, the United States could face a constitutional crisis over President Bush’s war policy in Iraq. The president and his allies seem to want this fight. Yet insisting upon a confrontation will be another mistake in a long line of bad judgments about a conflict that grows more unpopular by the day.

Last week’s narrow House vote imposing an August 2008 deadline for the withdrawal of American troops was hugely significant. So was the Senate’s 50-48 vote Tuesday afternoon to keep a call for pulling out of Iraq in its version of the supplemental appropriations bill to finance the Iraq War. In both houses of Congress, anti-war sentiment is strong, and growing.

The House vote was a test of the resolve of the new House Democratic leadership and its ability to pull together an ideologically diverse membership behind a plan pointing the U.S. out of Iraq.

To understand the importance of the House’s decision, one need only consider what would have been said had it gone the other way: A defeat would have signaled House Speaker Nancy Pelosi’s powerlessness to create a governing majority from a fragmented Democratic membership. In a do-or-die vote, Pelosi lived to fight another day by creating a consensus in favor of withdrawal that included some of her party’s most liberal and most conservative members.

The vote is only the first of what will be many difficult roll calls potentially pitting Congress against the president on the conduct of war policy. It confirmed that power in Washington has indeed shifted. Bush and his Republican congressional allies had hoped Democrats would splinter and open the way for a pro-Bush resolution of the Iraq issue. Instead, anti-war Democrats, including Web-based groups such as MoveOn.org, discovered a common interest with their moderate colleagues.

Oddly, the president’s harsh rhetoric against the House bill’s language setting a date for withdrawal may have been decisive in sealing Pelosi’s victory. “The vehemence with which the president opposed it made it clear to a lot of people that this was a change in direction and that it was significant,” said Rep. Chris Van Hollen, D-Md., chairman of the Democratic Congressional Campaign Committee. Tom Matzzie, the Washington director of MoveOn, saw the Bush effect rallying his own anti-war membership. “Bush is our worst enemy,” Matzzie said, “and our best ally.”

Now, Van Hollen argues, Bush’s “take-it-or-leave-it” approach to the bill is also “hurting the political standing of his Republican colleagues” in Congress by forcing them to back an open-ended commitment in Iraq at a time when their constituents are demanding a different approach.

Bush continued his effort to polarize the debate in his weekly radio address on Saturday, condemning the House vote as a “political statement” and urging Congress “to put our troops first, not politics” by sending him “a clean bill, without conditions, without restrictions, and without pork.”

The president’s uncompromising language and his effective imposition of an April 15 deadline for the funding bill — after that date, he said, “our men and women in uniform will face significant disruptions” — appear to have solidified Democratic ranks without rallying new Republican support. In the Senate vote, the key switches were in the Democrats’ favor. Sen. Ben Nelson, D-Neb., has often voted with Bush in the past but he stood with his party in support of a measure that includes calls for withdrawal and benchmarks for judging success.

Sen. Chuck Hagel, R-Neb., a longtime Bush critic, issued one of his strongest condemnations of the war over the weekend. “We essentially are ruining our National Guard. We are destroying our Army. We’re destroying our Marine Corps,” he told ABC’s George Stephanopoulos. “We can’t sustain this. … I will not accept the status quo.”

Hagel provided a critical vote for the withdrawal language on Tuesday. So did Sen. Gordon Smith, R-Ore., who faces re-election next year. Over time, anti-war pressures will grow on other Republicans who appear vulnerable in 2008, notably Sens. John Sununu, R-N.H., Susan Collins, R-Maine, and Norm Coleman, R-Minn.

While the House and the Senate must still reconcile their versions of the bill, it’s a near certainty that the final measure will contain language pointing toward withdrawal. And while Bush has the votes to sustain a veto, a growing weariness with the war is now affecting Republicans as well as Democrats.

The president’s refusal to acknowledge that the country has fundamentally changed its mind on Iraq makes it impossible for him to work with Congress on a sensible approach to a withdrawal that will happen someday — with or without a constitutional showdown.

E.J. Dionne’s e-mail address is postchat(at symbol)aol.com.

© 2007, Washington Post Writers Group

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