The Gay Liberation Front Manifesto was a revolution in consciousness when it was published in London in 1971, and it remains revolutionary today. It offers a radical critique of sexism and what we now call homophobia; as well as a pioneering agenda for social and personal transformation.

Amazingly, it was not written by high-powered intellectuals but by a collective of grassroots activists, driven by idealism and passion for the betterment of queer humanity. They included anarchists, hippies, leftwingers, feminists, liberals and counter-culturalists. The final text was a compromise between these different factions – and it shows. Some of it reeks of writing by committee. In places, the language is dated and inelegant. Some ideas are expressed too simplistically. Often you have to read between the lines to comprehend the full implications of what is being said. But despite these shortcomings, the central theses stand the test of time. They remain fresh, innovative, challenging and inspiring; stratospheres above the frequent mediocrity of today's lesbian, gay, bisexual and transgender politics.

I did not write the manifesto, but I was a GLF activist and involved in the discussions – and rows – about it. Inspired by the ideas of the black civil rights movement in the US, I had already conceptualised LGBT people as an oppressed minority, similar to black people, and believed that we had a comparable claim for equal treatment.

But the manifesto went much further. It was an eye-opener: expanding my civil rights perspective into a more radical critique of heterosexism, male privilege and the tyranny of traditional gender roles. It woke me up to the fact that queer liberation involved both social and personal change; that we could, within the bounds of existing society, begin to create an alternative culture that would liberate everyone, regardless of gender, sexuality or gender identity.

The manifesto aligned GLF with other liberation movements, such as the movements for women's, black, Irish and working-class freedom. Although critical of the misogyny and homophobia of the "straight left", it positioned the LGBT struggle as part of the broader anti-capitalist, anti-imperialist movement, striving for the emancipation of all humankind.

Most importantly, it argued that LGBT people needed to embrace and ally with feminism: "As we cannot carry out this revolutionary change alone … we will work to form a strategic alliance with the women's liberation movement … In order to build this alliance, the brothers in gay liberation will have to be prepared to sacrifice that degree of male chauvinism and male privilege that they still all possess."

The manifesto articulates a radical agenda for a non-violent revolution in cultural values and social institutions. It critiques homophobia, sexism, marriage, the nuclear family, monogamy, the cults of youth and beauty, patriarchy, the gay ghetto and rigid male and female gender roles.

As well as opposing the way things are, it outlines an alternative vision, including living communally, gender-subversive radical drag and non-possessive multi-partner open relationships. The message was: innovate, don't assimilate.

The manifesto's idealistic vision involved creating a new sexual democracy. Erotic shame and guilt would be banished. There would be sexual freedom and human rights for everyone – queer, bisexual and straight. In echoes of Franz Fanon and Malcolm X, it stated that the precondition for this social revolution is transforming our own consciousness and lives: "The starting point of our liberation must be to rid ourselves of the oppression which lies in the head of every one of us … we must root out the idea that homosexuality is bad, sick or immoral, and develop a gay pride."

Revolutionary, not reformist, the manifesto went beyond overturning homophobia and transphobia. Its aim was to end "male chauvinism" and the "gender system". Straight male hegemony was seen as the common oppressor of both women and queers. Subverting the supremacy of heterosexual masculinity was the key to genuine liberation.

The manifesto argues that much LGBT oppression results from the way we queers deviate from the socially prescribed, orthodox gender roles of masculine and feminine: "By our very existence as gay people, we challenge these roles." In most societies throughout most of history, men have been expected to be masculine and desire women; women are supposed to be feminine and desire men. LGBT people subvert the gender system. This is why we're persecuted. Our gender non-conformity threatens the gender system that helps sustain the hegemony of male heterosexuality and misogyny.

Queer men don't need to sexually subjugate women. Queer women don't need men to fulfil their erotic and emotional needs. This failure to meet traditional gender expectations is profoundly threatening to straight male supremacism: "The long-term goal of gay liberation, which inevitably brings us into conflict with the institutionalised sexism of this society, is to rid society of the gender-role system which is at the root of our oppression."

The manifesto positively celebrates gay deviance. It argues that the right to be different is a fundamental human right. The espousal of "radical drag" and "gender-bender" politics is a call to opt out of male privilege – an attempt to subvert the oppressiveness of heterosexual masculinity because we understood that it sustained both the subordination of women and same-sex love.The manifesto posited that LGBT people were often in the forefront of this important struggle: "Gay shows the way. In some ways we are already more advanced than straight people. We are already outside the family and we have already, in part at least, rejected the 'masculine' or 'feminine' roles."

Its core, ground-breaking message still rings true: that queer emancipation involves changing ourselves and then changing society. What's required is a revolution in culture, to overturn centuries of male heterosexual domination and the limitations of traditional gender roles. Then, and only then, will queers and women be truly free. Bravo!