THE JUXTAPOSITION last week was startling. On the same day, (a) voters in the Missouri primary overwhelmingly approved a state constitutional amendment establishing marriage as being exclusively between a man and a woman, and (b) a state judge in Washington ruled that the 19th-century writers of that state's constitution had made exclusively heterosexual marriage unconstitutional.

The vote in Missouri was not close: 71 percent in favor of the constitutional amendment, 29 percent against. Moreover, because of a hard-fought primary that wound up ousting Democratic governor Bob Holden, turnout was weighted to the Democratic side--roughly 58 percent Democratic voters, 42 percent Republican. And the opponents of the amendment--the pro-gay-marriage side--outspent backers of traditional marriage roughly 40 to 1--$400,000 to $10,000.

Missouri, the first state to hold a referendum since the Massachusetts supreme court imposed same-sex marriage over the objections of the governor and state legislature, confirmed that nothing has changed in voters' attitude to the idea. In 1998, it was Hawaii and Alaska; in 2000, Nebraska; in 2002, Nevada. In 2004, Missouri. The vote in every one of these states was more than 2-to-1 in favor of a constitutional prohibition of gay marriage. In Hawaii, the only state more Democratic than Massachusetts when it comes to electing Democrats as governors, senators, and congressmen, the vote was 69.2 to 28.6 percent in favor of an amendment overruling that state's supreme court. Between now and November 2, as many as 12 more states will hold constitutional referendums on marriage.

John Kerry, as it happens, was in Missouri the day after the same-sex marriage vote. It is a state in which, according to the daily political newsletter The Hotline, two of the three most recent polls show Kerry leading George W. Bush; the third has the two candidates tied. Missouri's 11 electoral votes, won narrowly by Bush in 2000, would make Kerry president if the 49 other states stayed with the same party as in 2000.

Asked in St. Louis about the previous day's vote, Kerry said he had no problem with it. He, after all, unlike George W. Bush, is the candidate who favors letting each state make its own decision. He didn't add that he was one of 14 senators, all liberal Democrats, who voted against the Defense of Marriage Act, signed into law by President Clinton in 1996. The purpose of DOMA was to let each state prohibit same-sex marriage even if a gay couple, married under some other state's law, demanded recognition of their union by invoking the Full Faith and Credit clause of the U.S. Constitution. In his 1996 statement opposing DOMA, Kerry said he believed the law to be unconstitutional.

John Edwards was not yet in the Senate when DOMA passed. But during the primaries he stated that he, too, would have voted against it. So on this, as on so many other issues, Edwards is in complete agreement with his running mate: He is in favor of the right of states to define marriage, but opposed to the federal legislation that sought to guarantee each state the right to keep its own definition.

In this straddle, Kerry and Edwards are perfectly in sync with their party's elite. The existence of the Defense of Marriage Act was the reason most frequently cited by Democratic senators earlier this summer for tabling a proposed constitutional amendment to preserve traditional marriage. Never mind that the Supreme Court is almost universally expected to rule DOMA unconstitutional some day, and that the amendment--which 46 of 49 Democratic senators voted to scuttle--is intended to let states keep traditional marriage even if the Supreme Court so rules.

Near the end of his acceptance speech at the Democratic convention, Kerry suddenly assumed a tone of high drama: "I want to address these next words directly to President George W. Bush: In the weeks ahead, let's be optimists, not just opponents. Let's build unity in the American family, not angry division. Let's honor this nation's diversity; let's respect one another; and let's never misuse for political purposes the most precious document in American history, the Constitution of the United States."

It was the biggest applause line of the speech. And it was, in its way, adroit. Everyone in the hall knew that, in the guise of calling for a civil debate, Kerry had accused the president of prostituting the Constitution by endorsing an amendment defining marriage as between a man and a woman.

Kerry was also demanding that the drive by federal and state judges to enshrine same-sex marriage not be opposed, or even debated. In a town hall meeting in Wisconsin the week after the convention, he repeated the warning: "We've got leadership that tends to try to drive a wedge between people. It picks one of the hot button, cultural issues and drives that at you, whether or not that's the most important thing on America's mind."

Events such as those last week in Missouri and Washington are making it less and less likely that Kerry, and the Democrats who cheered him in Boston, will get their wish. Kerry has made it clear that he and Edwards are personally opposed to same-sex marriage, so the debate will not be about the merits of this impending social change. Kerry, remember, has "no problem" with the Missouri vote. Yet everyone knows that, if left to themselves, judges like the ones in Massachusetts and Washington state will override the preferences of the 70 percent or so of Americans who likewise oppose same-sex marriage.

When it comes up in the fall campaign, as it certainly will, the issue will be what to do about this collision between democratic decision-making and judicial ambition. President Bush will have a clear answer: He will fight to preserve marriage, and his opponent will not. How does Bush know this? Kerry opposes changing the Constitution to preserve traditional marriage. He was one of 14 senators to vote against legislation to let states preserve it. And he is committed to appointing the kind of federal judges who created the problem in the first place.

That is the debate John Kerry can no longer avoid.

Jeffrey Bell and Frank Cannon are principals of Capital City Partners, a Washington consulting firm.

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