WHEN President Bush started making noises about World War III, he only confirmed what has been a Democratic article of faith all year: Between now and Election Day he and Dick Cheney, cheered on by the mob of neocon dead-enders, are going to bomb Iran.

But what happens if President Bush does not bomb Iran? That is good news for the world, but potentially terrible news for the Democrats. If we do go to war in Iran, the election will indeed be a referendum on the results, which the Republican Party will own no matter whom it nominates for president. But if we don’t, the Democratic standard-bearer will have to take a clear stand on the defining issue of the race. As we saw once again at Tuesday night’s debate, the front-runner, Hillary Clinton, does not have one.

The reason so many Democrats believe war with Iran is inevitable, of course, is that the administration is so flagrantly rerunning the sales campaign that gave us Iraq. The same old scare tactic — a Middle East Hitler plotting a nuclear holocaust — has been recycled with a fresh arsenal of hyped, loosey-goosey intelligence and outright falsehoods that are sometimes regurgitated without corroboration by the press.

Mr. Bush has gone so far as to accuse Iran of shipping arms to its Sunni antagonists in the Taliban, a stretch Newsweek finally slapped down last week. Back in the reality-based community, it is Mr. Bush who has most conspicuously enabled the Taliban’s resurgence by dropping the ball as it regrouped in Afghanistan and Pakistan. Administration policy also opened the door to Iran’s lethal involvement in Iraq. The Iraqi “unity government” that our troops are dying to prop up has more allies in its Shiite counterpart in Tehran than it does in Washington.