You may have already made your mind up about Declan McKenna. Eighteen but looking closer to 12, he hails from suburban southern England and specialises in anguished guitar ballads. The irresistible conclusion is he’s the Evil Music Industry’s latest lab-grown boy-strummer, in the tradition of Ed Sheeran, Jake Bugg, James Bay et al.

The theory falls apart, however, on first encounter with his actual music, which is jarring, genuinely troubled and troubling, and often
straightforwardly fucked up.

A case in point was last year’s break-out hit ‘Brazil’, which critiqued alleged human rights abuses by the Brazilian government in the run up to the 2014 World Cup. Correct me if I’m wrong but I don’t think Saint Ed of Ginger Hall has ever penned a tune about the downgrading of basic civil liberties ahead of a major sporting event (if you’re reading Mr Sheeran, feel free to take that as a challenge).

“You get comparisons to other singers and they often aren’t quite accurate,” McKenna tells me backstage at Dublin’s Academy. “The Ed Sheeran and Jake Bugg thing… often people see a boy with a guitar and want to lump them in a box. At one point SyCo [Simon Cowell’s boutique label] were interested in signing me!”

McKenna doesn’t regard himself as a social justice songwriter. Still, there is more depth to his lyrics than typical among up-and-coming troubadours.

“I would struggle to write a lovey-dovey pop song,” he says. “Don’t get me wrong – lovey dovey pop songs can be fantastic. Look at The Beatles – some of their best material was in that vein. That said, I would need to have some sort of concept to get started with. A lot of the songs I have written have political undertones. For me, art is political.”

McKenna began playing seriously at age 15 and has spent the past three years performing – or at least trying to perform – in venues around greater London.

“You’d ring up asking could you play and they’d say okay. And then I’d mention that I was under 18. Suddenly they weren’t quite so keen. I did a lot of open mic gigs. The quality varied a lot. There were nights you’d wonder, ’What am I doing this for?’ You feel you aren’t going anywhere.”

With ‘Brazil’, the singer suddenly was going somewhere. The single became an underground hit in the UK and brought attention from Sony Records. He repeated the feat with follow-up ‘Paracetamol’, a dark and frightening rumination on depression that side-stepped the traditional platitudes. In the months since, he’s been bunkered down working on his debut album with producer James Ford (Arctic Monkeys, Foals). To top it off, he was recently listed on the BBC Sound Of Poll of up-and-coming talents. The wheels are in motion.

“It’s strange because some of the songs on my album were written when I was 15,” says McKenna. “I’m 18 now. You change a lot in those years, don’t you? When we went into the studio, I was dealing with a lot of material that didn’t really reflect where I was at anymore. That was the challenge: to come up with stuff that spoke to me as I am now.”

He’s obviously of Irish background. Indeed, upon first hearing the name, you may have guessed “Declan McKenna” was another rootin’ tootin’ country crooner in the Nathan Carter tradition (that was certainly my assumption).

“All my grandparents were Irish,” notes the singer. “They came over to the UK back when people didn’t like the Irish coming in. My mum and dad were members of the Irish community. I loved it. I played gaelic football for my local team in Enfield.”

McKenna grew up in Cheshunt, a town of 60,000, some miles north of central London. For a footloose teen, it wasn’t the most inspiring of backdrops. “It’s pretty boring. Nobody works in the area – they all commute – so there aren’t any facilities. You have to go into London for everything.”

Given that he is so preposterously young, what does he make of the stereotyping of his generation as precious “snowflakes” too ready to take offence?

“The generation gap is focused on too much,” suggests McKenna. “It’s wrong to say people of my generation are spoiled and too sensitive. The younger generation is full of bright intelligent things doing stuff for themselves. Anyone who writes us off as lazy doesn’t know what they are talking about to be honest.” Declan McKenna’s latest single is ‘The Kids Don’t Want To Come Home’.