In a recent Supreme Court case, speaking for the 5-4 majority, Justice Anthony Kennedy wrote, "Laws of the kind before us raise the inevitable inference that the disadvantage imposed is born of animosity toward the class of persons affected." Thus the Court declared state laws barring same-sex "marriage" unconstitutional.

Okay, it hasn't happened—yet. But if the words sound familiar, it's because they came from Justice Kennedy's majority opinion in Roemer v. Evans (1996), in which the Court overturned a Colorado referendum barring special civil-rights protections and preferences based on sexual orientation; the Court claimed Colorado voters were biased against homosexuals. While the Supreme Court justices have not yet imposed gay "marriage" on America, decisions like Roemer make it inevitable—which is why the Congress must act swiftly on a constitutional amendment to protect the institution of marriage.

As we write, the Supreme stage is being set. Take the recent California case in which Superior Court Judge Richard Kramer ruled that laws barring gay "marriage" impermissibly deny the constitutional right to equality. That case, or one like it, could soon reach the high court—perhaps an appeal of the Massachusetts decision holding same-sex "marriage" a constitutional right, or a challenge to one of the 38 Defense of Marriage Act statutes enacted across America. It is not a question of if; it is a question of how soon.

At that point, does anyone think that the Supreme Court will not declare gay "marriage" a constitutionally protected right on the very grounds that Kennedy has already used in Roemer? Or, if the justices prefer, they might choose to rely on Kennedy's reasoning in Lawrence v. Texas (2003), which ...