Casey Gerald knew he was special from a young age. Not in a conceited or entitled way – being poor, black, gay, “a damn near orphan”, and from the wrong side of Dallas meant he would often be told otherwise – but special because his mother insisted he was. “And she was the most magical creature I ever knew,” he says, “like something from the movies.”

Gerald’s mother was, he later recognised, a manic depressive – “with big, crinkly, burnt-blond hair [that] made her look like a high-yellow Whitney Houston”. She left home and disappeared when he was 13. Some time before, Gerald’s football star father, the son of a renowned Texas preacher, became hooked on heroin only to then carousel in and out of prison. And so this gifted, athletic teenager ended up in the care of his grandmother and older sister – until a football scholarship to Yale became his ticket “to live America from the very bottom to the very top”.

Gerald and I talk via a video call from Los Angeles. Now 31, he is eloquent, handsome, thoughtful – the rags-to-riches poster boy for the American dream that his book, There Will Be No Miracles Here, sets out to dismantle. On the surface, his life reads as the elevator pitch for a Disney movie, the Horatio Alger myth beloved of pop culture and politicians; so much so that after meeting Gerald in 2016, former president George W Bush used his story in a speech to illustrate the plucky, inspirational, pull-yourself-up-by-your-bootstraps narrative that feeds the country’s identity.

“I think of my book as an intervention,” says Gerald. “To turn this American dream on its head is like being the warning on a pack of cigarettes: people will still smoke, but the way we’re taught to live our life in this society can kill you and it is killing people – even if they’re not dead, they are miserable, sad, depressed. We need to have a referendum on the American machine.”

What would the question be?

“How do we build a society where every kid has a shot? It’s as simple as that. One exceptional case [like mine] does not justify the suffering of 13 million American children who don’t have enough food or one in 30 who don’t have a stable place to sleep. My generation has inherited a country that doesn’t work any more.”

Gerald says he feels traumatised not only by his childhood, but by his belief that a Yale degree in political science, a prestigious MBA from Harvard Business School and a glittering career on Wall Street would save him. “For sure, it’s one of the reasons I’m in therapy.”

As a student, he took an internship at Lehman Brothers in the summer the bank filed for bankruptcy. Enthusiasm undimmed, after graduating he worked in economic policy and as an entrepreneur, but neither wealth nor success resolved his internal conflicts. “I had to write this book to understand what was wrong with me,” he says. “It’s a long journey.”

Gerald’s memoir is a nonlinear collection of memories and experiences, often unsentimental and stark, sometimes elegiac and elliptical. By writing about the dual burden and invisibility of being a black American man, he plays with a literary tradition that has been canonised by the likes of Frederick Douglass, Richard Wright, Ralph Ellison, James Baldwin, Ta-Nehisi Coates. It’s an ambitious exercise.

“There is a great tradition of people writing on the margins of society and I am grateful for them, but I had no interest in writing that kind of book,” he says. “I set out to tell the truth and understand why I and a lot of my friends were cracked up. I started this in 2016 and so the country and a lot of the world was cracked up too, but I was sad. I wouldn’t say I was having a nervous breakdown but I wasn’t far off.”

He wrote the first draft by hand, using “Morning Pages”, a writing style popularised by Julia Cameron’s book The Artist’s Way. This meant writing three pages of longhand every morning, on lined A4 paper, in a stream of consciousness. “I needed it to be a visceral exercise and lose myself in it.”

By 29, Gerald had successfully founded (and closed) MBAs Across America, a nonprofit organisation that matched business students with small businesses. Its aim was to “show that purpose and not profit is the new bottom line”. The model was made open source and taught as part of a curriculum at Harvard Business School.

According to New York magazine, Gerald seemed poised to either “run for national office in either party, become the youngest-ever CEO of a multinational business or produce and star in some viral reality show”. For now, he balks at the idea that he may consider a career in politics.

“I don’t have any political ambitions or willingness to be a politician,” he says, shaking his head. “I do believe I have been put on this planet to do real work but my priority is to be well. If I’m well, everything I do will be well.”

The experience of losing his grandmother last summer has underlined everything he wants his generation to rail against. “I was asked to write her obituary,” he explains, “and I got the draft [from his family] which was in essence: ‘she was born, she met this dude, she married him, she had seven of his children, she was a beautiful wife and mother and she died.’ And I thought: ‘holy shit, who is this? I thought she was a whole person and we’re supposed to go to her funeral and praise her for being submissive?’” He sighs. “I miss her so much. But eulogising her because she never complained? All that stuff, wow, that world is done. My sisters, my friends, my cousins, that is not a way of living for anyone.”

Gerald’s book mirrors the findings of a 2017 Pew study on the American dream that confirms “the myth of bootstrapping” – the fantastical notion that wealth and security can be achieved simply if you work and dream hard enough. The report reveals that social mobility between those at the bottom and those in the middle of American society has become increasingly harder, not easier. Given the choice, most families are happier to make ends meet and pay their bills than move up the economic ladder; this reads particularly true of African Americans who are stuck at the lowest levels and more likely to stay there and even potentially fall further behind from one generation to the next.

“Yes, this is Donald Trump’s America,” shrugs Gerald. “But let me be clear: I’m a black person, a queer person, my grandma’s grandfather was born a slave in Texas. Very few black people – if any I know – were shocked that Donald Trump was elected. Donald Trump may be the most American president we’ve ever had!

“For 200 something years we’ve been taught that the president was supposed to be better than everyone else – a Washington or Lincoln. Now is one of the few times we have a president that reflects a strong strain of depravity that has always been part of America. Life for people that Trump has been destroying with his policies – for poor people, people of colour, for immigrants – that has been intolerable and unsustainable for a long time.”

But Gerald isn’t without hope. “You can’t be a black American and not understand the extraordinary potential of the human spirit.” In any case, he believes a shift is under way. “Fundamentally, the way we are taught to be men in this country is a dead end and it’s changing – and I’m happy about that,” says Gerald.

His book, like the TED talk he delivered in 2016 titled The Gospel of Doubt, begins with the end of the world: a flashback of Millennium Eve when he was in church with his grandmother praying for the Rapture. “There’s a reason for beginning with that,” he says. “So much of my childhood was the world ending over and over again; no one called a family meeting and said: ‘Hey Case, how do you feel about your momma disappearing?’ It just happened and then you have to figure life out.”

Figuring things out included his place in the elite institutions he later found himself in, how he might make a difference, and his sexuality.

“I didn’t want to write a dissertation on being an oppressed gay person,” he says. “I wanted to bring worthy language to the beauty of loving another boy in a society that hates gay people – but that doesn’t mean I have to hate myself.”

The neighbourhood of Oak Cliff, where Gerald grew up, has barely changed in recent years, he says. Running east of downtown’s ever newer, ever shinier skyscrapers, it is still a predominantly African American area that straddles extreme wealth and deprivation.

“A lot of white people want to make the conversation about segregation, but I grew with incredible, dedicated black teachers, I had black crossing guards to get me across the street, there were hardly any white people and it did not occur to me then that I was inferior because I was black.

“Dallas, for all its faults, is not that much different to when I grew up except that there has been a continual material assault on the poor, working class, people of colour, that makes their lives materially more impossible. But that’s not a question of identity to me, that’s socioeconomics.”

Writing and talking about his experience, which he is clear “does not fetishise or commodify black bodies for entertainment”, has come at a cost to his mental health. “I don’t think it’s cathartic; catharsis implies purging and that didn’t happen. I can just see it clearly now,” he says.

“I don’t know what it will be like for us in 30 years or whether we will be happier. What I do know is that it will be different.”

• There Will Be No Miracles Here is published by Profile (£16.99). To order a copy for £11.99 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