Tracy K Smith is the poet laureate of the United States and a winner of the Pulitzer prize. Wade in the Water is, inexplicably, the first of her three collections to be published in the UK. The title is from a spiritual sung on the underground railroad that carried slaves to safety in the 19th century. Its centrepiece is a gathering of what are known as “erasure poems” – a strange term as what Smith is doing is the opposite of erasure. She is making visible the words of slaves and their owners, of African Americans enlisted in the civil war –these are found poems about people who were lost. Smith has pieced their correspondence together with the love of someone making a hand-stitched quilt.

The letter from Nashville in 1865 (below) is typical: brittle, misspelt and piercingly sad. It is a poem of salvage where salvage is no longer practical. I found myself wondering whether these were poems at all – and whether it matters. Their power to move is obvious, the injustices suffered undiminished by time. Elsewhere, Smith writes about history’s tendency to flee: “History spits, Go, go go, lurching at the horizon” (New Road Station). She is determined to hold history back, yet the outrage these poems occasion is familiar. They border on uncontroversial: no one reading this poetry could fail to be on the poet’s side.

For Smith, poetry is hospitable: accommodating whatever she is moved to write. Her work witnesses, protests and raises its own roof. Her contemporary protests take newer risks. There is a long, excellent and bracingly scandalised poem, Watershed, about the pollution of a river in Ohio by the chemical giant DuPont. The poem moves fast – another collage, folding in documentary and reportage and cutting into it with visionary, italicised moments where she almost levitates above her material: “I began rising through the ceiling of each floor in the hospital as though I were being pulled by some force outside my own volition. I continued rising until I passed through the roof itself and found myself in the sky…” Smith is a poet of many voices, from exalted to conversational: “They knew this stuff was harmful and they put it in the water anyway.”

The collection includes attractive, smaller-scale poems (especially Dusk, in which her daughter asserts her wobbly independence, seeming likely to become as much of a truthful spectator as her mother). Smith emerges as a poet in charge of her own creation myth and a recorder of destructive realities. Her offbeat, spiritual poems are her boldest – where it seems almost as though she is putting together a DIY Bible.

In Hill Country, God drives round in a jeep with the windows down (not a neocolonial, one hopes) and wonders whether there is “something larger than himself rearranging/ The air.” In Beatific, an arresting (in every sense) poem, a man obliviously crosses the road and there is the tiniest hint this down-and-out pedestrian could be a messiah. In The Angels, we meet a pair of Hells Angels: “Grizzled,/ In leather biker gear” who prove “Emissaries/ For something I needed to see”. They reek of “rum and gasoline” but, like many angels before them, tell us “not to fear”. This startling poem ends with other celestial sightings – laid on thick, poetic impasto. Yet the ending is beautiful and bare. It gives us “night” where “light” was expected: “My mother sat whispering with it/ At the end of her life/ While all the rooms of our house/ Filled up with night.”

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Letter from Norman Riley to Catherine Riley

Nashville, Tenn, 12 Aug 1865

Dear Wife,

I am in earnis about you comeing
and that as Soon as possible

It is no use to Say any thing about any money
for if you come up here which I hope you will
it will be all wright as to the money matters

I want to See you and the Children very bad
I can get a house at any time I will Say the word
So you need not to fear as to that So come
wright on just as Soon as you get this

I want you to tell me the name of the baby
that was born Since I left

I am your affectionate Husband untill Death