It’s bound to set off yet another political fight, but the Iowa Supreme Court today declared that state’s ban on gay marriage unconstitutional:

DES MOINES — Iowa became the first state in the Midwest to approve same-sex marriage on Friday, after the Iowa Supreme Court unanimously decided that a 1998 law limiting marriage to a man and a woman was unconstitutional. The decision was the culmination of a four-year legal battle that began in the lower courts. The Supreme Court said same-sex marriages could begin in Iowa in as soon as 21 days. The case here was being closely followed by advocates on both sides of the issue. While the same-sex marriage debate has played out on both coasts, the Midwest — where no states had permitted same-sex marriage — was seen as entirely different. In the past, at least six states in the Midwest were among those around the country that adopted amendments to their state constitutions banning same-sex marriage. “The Iowa statute limiting civil marriage to a union between a man and a woman violates the equal protection clause of the Iowa Constitution,” the justices said in a summary of their decision. And later in the ruling, they said: “Equal protection under the Iowa Constitution is essentially a direction that all persons similarly situated should be treated alike. Since territorial times, Iowa has given meaning to this constitutional provision, striking blows to slavery and segregation, and recognizing women’s rights. The court found the issue of same-sex marriage comes to it with the same importance as the landmark cases of the past.”

It didn’t take long, though, for the political games to start:

Opponents of same-sex marriage criticized the ruling.

“The decision made by the Iowa Supreme Court today to allow gay marriage in Iowa is disappointing on many levels,” State Senator Paul McKinley, the Republican leader, said in a statement on The Des Moines Register’s Web site. “I believe marriage should only be between one man and one woman and I am confident the majority of Iowans want traditional marriage to be legally recognized in this state.” He added: “Though the court has made their decision, I believe every Iowan should have a voice on this matter and that is why the Iowa Legislature should immediately act to pass a Constitutional Amendment that protects traditional marriage, keeps it as a sacred bond only between one man and one woman and gives every Iowan a chance to have their say through a vote of the people.” Advocates of same-sex marriage said they did not believe opponents had any immediate way to overturn the decision. A constitutional amendment would require the state legislature to approve a ban on same-sex marriage in two consecutive sessions after which voters would have a chance to weigh in.

So, for the moment at least, there’s been a victory for marriage equality in the Mid-West.

Whether it will stand, and whether it will lead to changes elsewhere, remains to be seen.