This is the first edition of Audre Lorde’s writing to be issued by a UK publisher, which isn’t to say it will be the first time British readers will have encountered her work. Even those who haven’t yet engaged with her incandescent prose and poetry might have come across individual lines, quoted in other writers’ books and essays, and on social media, such as the titular exhortation: “My silences had not protected me. Your silence will not protect you.” Other lines include: “The master’s tools will never dismantle the master’s house”; “Black feminism is not white feminism in blackface”; and “I am not free while any woman is unfree, even when her shackles are very different from my own. And I am not free as long as one person of colour remains chained.”

These and other excerpts have been posted, tweeted and pinned in part because of their ongoing relevance. Lorde seems prophetic, perhaps alive right now, writing in and about the US of 2017 in which a misogynist with white supremacist followers is president. But she was born in 1934, published her first book of poetry in 1968, and died in 1992. Black, lesbian and feminist; the child of immigrant parents; poet and essayist, writer and activist, Lorde knew about harbouring multitudes. Political antagonists tried, for instance, to discredit her among black students by announcing her sexuality, and she decided: “The only way you can head people off from using who you are against you is to be honest and open first, to talk about yourself before they talk about you.” Over and over again, in the essays, speeches and poems collected in Your Silence Will Not Protect You, Lorde emphasises how important it is to speak up. To give witness: “What are the words you do not yet have? What do you need to say? What are the tyrannies you swallow day by day and attempt to make your own, until you will sicken and die of them, still in silence?”

These remain urgent questions – a battle cry, I might call it, except that part of the power of Lorde’s writing comes of her manifest vulnerability. In the remarkable essay “Man Child”, she writes about raising a son, Jonathan, who was bullied by his third-grade classmates. Hearing of the bullies’ cruelties, she says that “an interesting and very disturbing thing” happened:

My fury at my own long-ago impotence, and my present pain at his suffering, made me start to forget all that I knew about violence and fear, and blaming the victim, I started to hiss at the weeping child, “The next time you come in here crying … ” and I suddenly caught myself in horror.

Stopping herself, she avoids giving Jonathan “that first lesson in the corruption of power, that might makes right”. Instead, she tells him about the after-school fights she also fled when she was a child terrified of breaking her glasses. “Did I ever tell you about how I used to be afraid when I was your age?” she asks, and is met with the child’s combined “relief and total disbelief”. “I am thankful that one of my children is male, since that helps to keep me honest,” she notes. “Every line I write shrieks there are no easy solutions.”

With adults, too, she fought to maintain the generosity of openness. Lorde writes that at one point, she resolved “never again to speak to white women about racism”, that it was “wasted energy because of destructive guilt and defensiveness”. But she explains this more as part of a 1979 letter to Mary Daly, a white feminist author of a book exploring myths and legends of female power. Lorde tries to show in the letter why it’s painful that in the book Daly mentions women who aren’t white only as “victims and preyers-upon each other”, and reserves quoting Lorde and other black writers for the one chapter on genital mutilation in Africa. Although Daly had sent her the book in the first place, Lorde hesitated to reply because, she says:

The history of white women who are unable to hear Black women’s words, or to maintain dialogue with us, is long and discouraging. But for me to assume that you will not hear me represents not only history, perhaps, but an old pattern of relating, sometimes protective and sometimes dysfunctional, which we, as women shaping our future, are in the process of shattering and passing beyond, I hope.

Lorde’s hope, in this instance, wasn’t met; Daly never replied. One wonders if she would reply today. As recently as January, when one of the organisers of the Women’s March on Washington issued a statement asking white participants to “understand their privilege, and acknowledge the struggle that women of color face”, subsequent news articles quoted white protesters who called the statement divisive and unwelcoming. Out of context, the following words from a 1979 speech by Lorde could be mistaken for a speech given in 2017:

Women of today are still being called upon to stretch across the gap of male ignorance and to educate men as to our existence and our needs. This is an old and primary tool of all oppressors to keep the oppressed occupied with the master’s concerns. Now we hear that it is the task of women of colour to educate white women – in the face of tremendous resistance – as to our existence, our differences, our relative roles in our joint survival.

Still, Lorde kept speaking up by writing about difference and possibility, and the ongoing struggle “to make common cause with those others identified as outside the structures in order to define and seek a world in which we can all flourish” – intersectionality before the term existed.

While reading Your Silence Will Not Protect You, I was reminded of the musician Vijay Iyer’s comment: “It becomes necessary for an artist of colour in the west to defiantly announce to the world: I am a fact.” In this new, illuminating collection, Lorde is a fact, and the truth of her writing is as necessary today as it’s ever been.

• Your Silence Will Not Protect You is published by Silver. To order a copy for £11.04 (RRP £12.99) go to guardianbookshop.com or call 0330 333 6846. Free UK p&p over £10, online orders only. Phone orders min p&p of £1.99.