When Barack Obama came out in support of gay marriage earlier this month, there were many who heralded it as a turning point in the history of equal rights. Symbolism plays a major part in the struggle for acceptance. Just as John F Kennedy finally adopted the cause of the civil rights movement, the gay rights lobby can now claim that the White House is officially on side (even if it suspects Mr Obama had been so privately for a long time).
Legislative change is what finally frees a victimised group from state-sanctioned discrimination. But laws tend only to be altered once a significant bulk of the population accepts, tolerates and even celebrates a community's differences.
Today's International Day Against Homophobia and Transphobia is a key part of keeping the gay rights flame alive. All over the world people will make small actions which, taken as a whole, remind us of the victories won and also the amount of work that needs to be done.
"[The day] brings to attention just how much homophobia and transphobia there is in the world," said Lance Price, executive director of the Kaleidoscope Trust, which campaigns on lesbian, gay, bisexual and transgender issues. "Huge strides have been made in the UK and other countries, but elsewhere the challenges are massive."
Often it seems that international days to promote causes are picked arbitrarily – but there is a good reason why today represents the fight against sexual prejudice. It was on 17 May 1990 that the World Health Organisation finally removed homosexuality from its "International Classification of Diseases" list.
The world has come a long way. Civil unions, gay marriages, the repeal of discriminatory laws and punishments for homosexuality have gathered pace across the world. Even in the US, where evangelical Christianity clamours to dominate the debate over sexuality, the acceptance of gay relationships has undergone a radical transformation. Ten years ago, an average of just 45 per cent of Americans supported gay marriage; now that figure is an average of 56 per cent.
But the picture is not all pink. There are still at least five countries which retain the death penalty for homosexuality, while almost half of Africa's 52 nations impose criminal punishment.
"We have come so far, and we have a responsibility to try to challenge these things elsewhere," says Matthew Todd, the editor of Attitude magazine. "It's a simple human rights issue."