Ashley Joiner’s Are You Proud? is a vivid and engaged docu-celebration of the LGBT rights movement in the UK, from the partial victory of the 1967 Sexual Offences Act, through to Stonewall in the United States and the Gay Liberation Front here in the 1970s – though, oddly, no mention of the wretchedly vindictive legal action against Gay News – through to the HIV-Aids crisis, Margaret Thatcher’s late spite-attack against homosexuals in the late 80s with Section 28, and the current situation in which gay campaigners fear that the annual Pride march is at risk of a corporate takeover, with Barclays emblazoning its own logo with rainbow colours. (What 1980s anti-apartheid campaigner would have predicted that?)

The recent case of two gay women beaten up on a London bus is a reminder that this is not a matter of “identity politics”: it is about real prejudice and real violence against real people. Joiner’s film is a fierce reminder of that, and we hear from a number of witnesses, including Lisa Power, Michael Cashman, Chris Smith and the heroic veteran Peter Tatchell.

Yet, like love, the course of LGBT rights campaigning does not always run smooth and the film gives an extensive, but incomplete history of internal disagreements. It falls to Tatchell to point out that, while campaigners were justifiably enraged by the 2016 mass shooting in Orlando, political correctness precluded interest in the Islamist massacres of gay people in Africa and the Middle East. The film boldly includes a spokesperson for Black Pride who suggests that the LGBT movement has too often been a white movement in which black people are marginalised – although the film does not address the contention that some lesbians now feel alienated.

As for the obvious problem involved in opposing Islamophobia and homophobia at the same time, well, Islam is hardly the only religion or ideology officially antipathetic to gay people, and there has to be room for reformation and evolutionary growth.

• Are You Proud? is released in the UK on 26 July.