The recent debates in Massachusetts and San Francisco are evidence that legalizing gay marriage is possibly the most important civil rights question of our time. It is emblematic of the United States’ – and perhaps democracy’s – most enduring dilemmas regarding the relationship of church and state and the parameters of equality.

Throughout American history, legislatures have changed and manipulated the definition of marriage to convey the power of dominant social groups and impede perceived threats. Today’s debate is no exception. Legalizing gay marriage guarantees social and legal rights and reaffirms the constitutional separation of church and state.

Gay rights activists were among the first in this debate to recognize that marriage in the United States is not a perfect institution. As Britney Spears so ably demonstrated, the so-called “sanctity” of marriage does not offer, or require, success. For better or worse, marriage is the primary legal unit on which many laws are based, including child care, health care, property rights and taxes. In addition, it has become the litmus test for social equality.

Churches, whose membership is constitutionally protected, may continue to shun same-sex marriages, but the state should not use marriage as a weapon of oppression. As the classical American philosopher George Santayana wrote, “Those who cannot remember the past are condemned to repeat it.”

As recently as the 1970s, many states did not recognize interracial marriage. In the 1967 case that struck down those laws, Loving v. Virginia, the U.S. Supreme Court wrote, “The freedom to marry has long been recognized as one of the vital personal rights essential to the orderly pursuit of happiness by free men. … Marriage is one of the ‘basic civil rights of man,’ fundamental to our very existence and survival.”

The prohibition of same-sex marriages is emblematic of our culture’s underlying intolerance and deep-seated fear of change. Legal discrimination against homosexuality is indefensible and will not survive the next generation. The debate is a sign of hope. It was triggered by the fear of near change and brings to light the prejudices we must overcome.