Back in the primary season, one of Senator Kerry’s press aides was challenged by a reporter who characterized Mr. Kerry’s stand on Iraq as “ambivalent.” Well, that was all right, the aide said. The voters are ambivalent.

And so they are – at least if you’re looking at Democrats. Pollster Scott Rasmussen asked an ingenious question that makes the point. Should we be using more military force in Iraq, about the same amount of military force, or less military force? The answers may be surprising. A plurality of 39% said more military force, 26% said the same amount, and only 22% said less military force.

Republicans and Democrats, as you might expect, take very different stands – which provide a good backdrop for assessing Mr. Kerry’s and Mr. Bush’s performance in the first presidential debate. Bush voters are overwhelmingly for more force (51%) or the current level (37%).In other words, when Mr. Bush called for using as much force as it takes to prevail, 88% of his voters are with him.

Kerry voters, in contrast, are polarized. Some 40% say we should be using less force – presumably, most of these want us out altogether. But 28% say they want more military force, with 15% saying the same level. If Mr. Kerry wants to rally his supporters, he must appeal to both those who want to win and those who want to get out.

Appealing to people with opposite views is difficult. Some of the masters could do it. Faced with two utterly inconsistent proposals, Franklin Roosevelt told his speechwriters, “Weave the two together.” He knew how to do it, and so did Bill Clinton. Mr. Kerry, in his Senate speeches, on the campaign trail, and in his rare television interviews, has been less artful. In the debate, he did a better job. Boxed in by the Bush campaign debate negotiators to 120-, 90-, and 60-second responses, he spoke more pithily than he usually does and in less stilted language. But the result was still ambivalence.

At one point, Mr. Kerry said, “The president made a mistake in invading Iraq.” Then, asked if the troops in Iraq were dying for a mistake, he said, “No, and they don’t have to, provided we have the leadership that…I’m offering.” In his presumably carefully prepared closing statement, he said that “parents of kids in Iraq, you want to know who’s the person who could be a commander in chief who could get your kids home and get the job done and win the peace.” Then, less than 60 seconds later, he said: “I’m not talking about leaving. I’m talking about winning.” Win or get out: Take your pick.

Much of what Mr. Kerry offers unambivalently is simply not realistic. You might believe that his appointees would train Iraqi forces and rebuild infrastructure more rapidly than Mr. Bush’s – though Mr. Kerry’s managerial experience is limited to a prosecutor’s office, his Senate staff, and this campaign. But his proposal for a summit to bring in allies is unrealistic. Summits require extensive preparation to succeed. Countries with serious militaries not in Iraq have made it plain they won’t change their minds. Nor could they make much difference.

Mr. Kerry complained that American troops comprise 90% percent of coalition forces. But in any large-scale deployment, American troops will predominate. Other nations simply do not have large forces with out-of-area capability. Only in small coalitions is America a junior partner, as it is in Haiti, where capable Brazilian troops take the lead role. But Brazil, the world’s fifth most populous nation, has few troops it could spare for Iraq.

Mr. Kerry’s Vietnam-era tendency to consider America the problem and not the solution showed up at several points. The International Criminal Court he favors would subject American troops to French prosecutors and Swedish judges, which is why Mr. Clinton never bothered to submit it to the Senate – it’s a nonstarter. Mr. Kerry opposes development of bunker-blasting nuclear bombs as “nuclear proliferation,” though we’re not going to give them away and despite their usefulness against possible targets in a nuclear Iran or North Korea. He says the president has the right to make preemptive strikes, but “if and when you do it, Jim, you have to do it in a way that passes the test, that passes the global test.”

Suddenly the ambivalence is gone – and we have a clue as to whether a President Kerry would win or get out.