The Kerry campaign, which pledges to re-energize American diplomacy, does not confuse this goal with being sweet to foreigners. Richard Holbrooke, one of the front-runners for a top foreign policy position if John Kerry wins the presidency, used the iron fist in the Balkans as much as the velvet glove during the 1990s. And last week Sen. Joe Biden, Holbrooke's chief rival, chastised French President Jacques Chirac for having "an ego as big as this room," adding that the French have "been a pain in the you-know-what."

As for our other cherished European allies, Biden had this to say: "In the 30 years I've been a senator, there is very seldom an initiative that is generated from the European community to take action on almost anything."

Maybe, as a future Cabinet official, Biden will lecture us on the irrelevance of "Old Europe"?

Biden's comments, at a public meeting of the Council on Foreign Relations, also shed some light on the central tension in Kerry's Iraq position. Kerry has said repeatedly that he wants to "win" in Iraq, meaning that he wants stability and some form of democracy. But he also says simultaneously that (a) President Bush has undermined the Iraq mission by failing to commit enough troops and that (b) a Kerry administration would hope to start bringing troops home six months after taking office. The way out of this contradiction is to promise that allied troops will shoulder some of America's burden. Which raises a question for Kerry's aspiring secretary of state: How would allies be persuaded to come forward?

Biden's answer came in the form of a long anecdote. (Warning to State Department correspondents: Many of Biden's answers come in the form of long anecdotes.) The story featured a European leader who tells Biden he wants Kerry elected, to which Biden shoots back, "Be careful what you wish for." Within two weeks of Kerry's election, the senator continues, he'll be telling his friend to help more in Iraq. What if we say no, the European asks. Biden retorts: "If you would not act at all, I'd advise Kerry to leave Iraq."

This would be a fairly risky sort of brinkmanship. Biden is right that Europeans have plenty at stake in Iraq, and that they ought to contribute more than they've done so far. But this is bit like saying that Americans can't afford their entitlement programs, so they ought to reform them. Both statements are true, but logic doesn't necessarily drive action.

It's just about certain that Biden's ultimatum would yield no results in France. Chirac's anti-American foreign policy is supported by 76 percent of his countrymen, even though only 36 percent approve of him generally. The Economist recently asked Michel Barnier, the French foreign minister, whether French soldiers might go to Iraq if Kerry became president. "Never," he said flatly.

Other allies appear scarcely more promising. Spain's Socialist prime minister has boosted his popularity by pulling Spain's soldiers out of Iraq. The leaders of Britain, Poland and Italy face public pressure to withdraw, too, and they are not going to increase their commitments. "For the 368th time, no, we are not sending any German soldiers to Iraq," a German Foreign Ministry official told the Associated Press on Friday.

In sum, it seems unlikely that a Kerry administration could persuade allies to contribute substantially more troops. So what about training more Iraqi soldiers? This would certainly help, but unfortunately building security forces takes time: Last week, the respected International Institute for Strategic Studies estimated it would require five years to train Iraqi forces to the point that they could take over from Americans. Besides, Iraqi units will never be likely to spearhead the tough counterinsurgency missions. If you send Shiite units to attack Sunnis, you deepen Iraq's dangerous religious split. If you send Sunnis to attack Sunnis, you can't count on orders being followed.

If neither foreign nor Iraqi troops come to the rescue, a President Kerry might face a choice: Take back his election talk of bringing soldiers home, or take back his election talk of winning. Kerry is a responsible leader surrounded by a tough foreign policy team, and in the past few days I've edged closer to the view that he would not abandon Iraq prematurely. But if his team really did present the Europeans with a Biden-style ultimatum -- you get into Iraq or we get out -- it would risk creating a dynamic that would lead to a U.S. withdrawal and terrifying anarchy.

Supporting a presidential candidate is never without risk, and the possibility that Kerry is less than determined to win in Iraq is the most significant risk that he poses. On the other hand, George W. Bush poses risks that are arguably each smaller but almost too numerous to count. His fiscal policy is reckless; his stance toward congressional pork-barreling is spineless; his instincts on the environment, gay marriage, abortion rights and civil liberties are distressing. And although his determination to prevail in Iraq seems firmer than Kerry's, his capacity to do so is less obvious. Sometimes his team appears to be learning from its errors in Iraq. But then sometimes it's tone-deaf. Last week, a Pentagon spokesman insisted, against all evidence, that his department's policy was not connected -- no, not in any way at all -- to the Abu Ghraib prison scandal.