Homosexuality used to be considered either a pathology (it was classified as a mental disorder by the American Psychiatric Association until 1973) or a misguided and sinful “lifestyle choice.” But cultural attitudes have shifted dramatically in recent decades, and millions of Americans now understand that homosexuality is neither a disorder nor a bad decision; it is an involuntary attribute, like race or gender, which has no bearing on an individual’s capacity to lead a productive, well-adjusted existence. The right to marry a partner of one’s choice, on the other hand, is central to the good life. As the United States Supreme Court declared in Loving v. Virginia, the 1967 case that abolished race-based restrictions on marriage in this country, “Marriage is one of the ‘basic civil rights of man,’ fundamental to our very existence and survival.” Significantly, the Supreme Court of Massachusetts cited Loving in Goodridge v. Department of Mental Health, the 2003 case in which it ruled that the Massachusetts constitution requires the state to extend the same marriage rights to heterosexual and same-sex couples.

Four principal problems cloud the legal status of same-sex couples in this country. First, marriage is governed by state law, and most states do not recognize marriages between homosexuals. Same-sex marriage is legal today only in California and Massachusetts. Either by statute or through their constitutions, 44 states now define marriage as a union of a man and a woman. Many of these discriminatory laws were passed in recent years, as progress in a few states has been met by backlash in many more.

Second, civil unions and domestic partnerships, which were devised to give same-sex couples a legal alternative to civil marriage, are in fact a second-best alternative. Only a handful of states allow same-sex couples to enter into civil unions or domestic partnerships, and not all of these provide full spousal benefits. Separate is rarely equal.

Third, same-sex couples face a patchwork of provisions varying widely from state to state. States with laws against same-sex marriage are not required to recognize same-sex marriages or civil unions validly contracted in other states. Any state can voluntarily decide to recognize same-sex marriages from other states, as New York now does, but there is no enforceable requirement for interstate recognition. A same-sex couple married in California, for example, might have no legal standing in Utah. Divorce presents another set of complications. Out-of-state couples who traveled to Massachusetts or California to be married cannot be divorced in their state of residence if the marriage was never recognized in that state to begin with. Estranged couples can return to Massachusetts or California to dissolve their marriage, but both of these states have residency requirements for divorce, meaning that one or both spouses would have to live in the state for up to a year before filing for divorce. Some states that grant civil unions also have residency requirements for terminating the union, as is the case in Vermont.

For many same-sex couples, as for heterosexuals, the idea of life partnership often incorporates children. Since most same-sex couples cannot marry in their state of residence, a complicated and intrusive process of second-parent adoption is usually necessary to establish joint parental rights. But another patchwork of provisions is found in state adoption laws. While a few states prohibit discrimination on the basis of sexual orientation in adoption proceedings, a number of others bar gay individuals and same sex-couples from adopting. In most states, loosely defined regulations place same-sex parents at the mercy of local judges and adoption officials.

Finally, neither gay marriages nor civil unions are recognized by the federal government. This means that same-sex couples are denied the 1,138 federal benefits, rights, and privileges that, according to a 2004 study by the Congressional Budget Office, attach to civil marriage. Many of these benefits relate to property rights, taxation, and other material matters that can make a significant difference in a family’s financial status. Immigration is another sticking point: a United States citizen who is married can sponsor his or her non-American spouse for immigration into this country, a prerogative not shared by same-sex couples. Internationally, six countries—Belgium, Canada, the Netherlands, Norway, Spain, and South Africa—have legalized same-sex marriage, and a handful of others offer many rights to same-sex couples, though they stop short of marriage.

As heterosexual parents of two children, my husband and I take for granted an array of rights and privileges that are routinely denied to same-sex couples. Wherever we go in this country—or in the world, for that matter—we are legally married, whereas a gay couple might incur legal risks through the simple act of crossing a state line. We’ve never had to pay a lawyer to help us determine if our New York State marriage license will be recognized in another state. I can’t be forced to testify against my husband in a court case, and he has the right to make decisions on my behalf should I become incapacitated. We file money-saving joint tax returns at the municipal, state, and federal levels, and we get a number of tax credits as a married couple with children. Neither of us will ever be barred from a hospital room where one of us lies sick or injured, and both of us are entitled to wrongful death benefits. We share health and other insurance plans. If we ever consider relocating for career purposes, we won’t need to worry about retaining our parental rights, and should we divorce, joint custody will never be an issue so long as we both behave responsibly. But that is just the point: for same-sex couples, being responsible, law-abiding, tax-paying citizens is not enough. When it comes to marriage and family life, only straight people enjoy equal protection under the law.

A Republican victory in November will spell disaster for the civil rights of same-sex couples. John McCain recently endorsed efforts to ban same-sex marriage in California, and he advocates leaving states free to determine their own approaches to marriage—a recipe for continued inequality. His running mate, Sarah Palin, has supported a constitutional amendment to ban gay marriage in Alaska, where she is the governor. Barack Obama and Joseph Biden both oppose gay marriage but support full spousal rights under civil unions and domestic partnerships. Separate but really equal would be a welcome step forward, but it will not solve the problem of federal recognition. Redressing the second-class status of same-sex couples will continue to be an uphill battle in the years ahead. Ultimately, as the Supreme Court of Massachusetts put it in Goodridge, “history must yield to a more fully developed understanding of the invidious quality of the discrimination.”