Peter Tatchell: A long slog to the promised land of equality – and love

My friend Robin Tyler likes to joke that there is no such thing as same-sex marriage, because after marriage sex is never the same. Witticisms aside, she and her long-time partner Diane Olson were the original plaintiffs who bought the successful legal action that overturned the ban on gay marriage in California last year.

Together with 18,000 other gay and lesbian couples, Robin and Diane took advantage of the new legal dispensation. They got married. What joy. It was, in Robin's words, "a simple, elegant, lesbian Jewish wedding," held at the Beverly Hills Courthouse, where they had previously applied for a marriage licence – and been rejected – every year since 2001.

For Robin and Diane, the legal battle over Proposition 8 is not about whether marriage is a good institution or not. The real issue for them is equality: the right of all US citizens to be equal under the law, regardless of sexual orientation. On a personal level, it is about public recognition and respect for the commitment they have made to each other.

The battle for same-sex marriage has involved years of litigation in dozens of states. It echoes the protracted legal battles by the black civil rights movement to quash the laws against inter-racial marriages. These laws were struck down by the California Supreme Court in 1948, but only finally outlawed in all states in 1967.

It was a long, hard slog by African-Americans to win legal equality, and so it is proving for lesbian and gay Americans too. Hopes and victories, followed by disappointments and setbacks.

But to paraphrase Dr Martin Luther King Jr, one day gay Americans will get to the promised land. They will secure same-sex marriage, legal protection against discrimination and an end to the restrictions on gay people serving in the US military. These victories will help make the US a kinder, more tolerant nation, to the benefit of all Americans. As Dr King often reminded us: "Injustice anywhere is a threat to justice everywhere."