Cobain had burst to fame in 1991 with his band, Nirvana. For a fragmented generation of teenagers he was more than just a pop star. He was a focal point that united them. Nirvana's second album, Nevermind, released in 1991, rejuvenated popular music as a transatlantic force after a decade in which America and British tastes had grown more polarised.
In the Eighties, America produced stars such as Madonna and Michael Jackson; the powerhouse of MTV. But many young people found this all too bland and homogenous. The music which fired British youth in the 1980s - the Smiths, Happy Mondays, the Stone Roses - was greeted like a case of rabies when it was unloaded at JFK.
Cobain managed to fill this gap. He was angry, soulful and unformed, bashing out songs on his guitar with a few friends. Yet he was also unashamedly interested in pure pop songs. Bjorn Again, the Abba imitation band, was one of his favourites. He sang confessionally, like a soul singer, but wasn't interested in being esoteric for the sake of it. He was serious, but did not betray a hint of pomposity.
His dress was unkempt and he looked like a rebel, an inheritor of punk. Yet he was impossible to tie down or confine within the traditional boundaries of pop. He was sensitive, a father. From this mass of contradictions came Cobain's success: passion or soul or anger - whatever it was, it made Nirvana the saviours of rock'n'roll for a new generation.
And then he chose to kill himself and left them wondering why.
He has been dead a year now, though you would think it was longer: death had always been such an intrinsic part of his music that we were halfway toward being prepared for it. The Nirvana song "I Hate Myself And I Want To Die" was surely a joke, you thought, until you combed through the scrawled suicide note, now reprinted on T-shirts. "Sometimes I feel as if I should have a punch-in time clock before I walk out on stage ... I need to be slightly numb in order to regain the enthusiasm I once had as a child."
The impact of his death on a generation of young people should not be underestimated, even though it probably has been by countless parents. A lot of teenagers will remember exactly what they were doing when they heard the news of Cobain's death. That weekend there were public and private memorials: candlelit vigils, fans carved his name in their arms, the Samaritans tooks stacks of calls, and teenagers in droves retired to their rooms to listen to Nirvana, ponder Cobain's picture and ask why he left them.
Now, a year on, Britain has another potential rock'n'roll tragedy in the making. Richey Edwards, of the band Manic Street Preachers, which played in the same vein as Nirvana, has been missing for more than two months. His car was found at a notorious suicide spot next to the Severn Bridge. It has all the uncomfortable echoes of events last April.
The combination of Edwards's disappearance and Cobain's suicide has had a profound effect on the nation's youth, judging by the avalanche of letters sent to NME, the pop music paper, which devoted a page this week to letters of concern about Richey Edwards.
One might think this was a generation that feels sympathy with suicide as a response to the times. They do. But it is not as simple as that. A year after Cobain's death his fans are still beset by confused emotions. They miss him, but they don't hide their anger with him for taking his life. They are passionate about him but are also pragmatic: they cannot comprehend the grandiloquence of his suicide.
Stella, 20, is a sales assistant in a charity shop. She heard that her hero was dead while she was at work.
"Everything stopped still. I just stood there, I was gutted. I didn't get emotional or cry or anything, not then. I was just in a state of shock I think. No one else really got it - no one at work knew who he was. He wasn't their sort of thing at all. But there was no one who ever affected me like that before him. No one. There won't be again, I know it. No one could fill his shoes."
Stella was introduced to Nevermind by her sister, and had bought tickets for the 1994 tour that never reached Britain. A few months ago, she was thinking about how she could show what Kurt meant to her.
"I just suddenly thought about changing my name," she says excitedly, as though reliving the impulsiveness of that day. "It just seemed like the biggest tribute, you know? I thought, well, I could do the ultimate and change it to Nirvana. But I threw out the `n' and the `r' and it really seemed to work."
Stella became Ivana. "My family and friends all think I'm a bit mad, really." She says she will spend the anniversary of his death lying on her bed, listening to the albums, watching the videos, thinking about Kurt.
"It's his lyrics, they're just so realistic, they really speak to you about what happens in your life. One of my favourites is the song "Dumb", that line "I think I'm dumb/ Maybe just happy". I can really relate to that because people think I'm stupid sometimes.
"I don't think Kurt was cowardly to kill himself. But it was selfish. I've thought about this a lot, and he shouldn't have done it, leaving his family and everything. It's just wrong. It's bad for his fans, too, but for his family ... it's just wrong."
Luke, 14, is less critical. At school, he plays bass, with his friend on guitar, and they have taught themselves Nirvana songs. He thinks money was at the heart of Cobain's tragedy: "It's the same thing as with the Sex Pistols, they hated rich people and then they got rich."
"If I'm unhappy, I just go to my room or walk the dog. Kurt couldn't do that. And you just imagine if you were in a room and someone kept going [clicks his fingers rhythmically]. You'd want to kill them. That's what the opening riff of "Smells Like Teen Spirit" must have been like for him. It would drive you mad, wouldn't it?
"If it wasn't for that song, people might not have heard of Nirvana. They'd probably still be playing little clubs supporting Mudhoney or Sonic Youth. And I wouldn't have heard of them, I'd still be listening to Guns 'N Roses. He'd probably be alive if everything had gone that way."
Luke found out the news as he was setting off on holiday. "We were going to Wales, and I was going to the newsagent's to get some sweets for the journey, and I heard it on the radio in the shop - `Rock star Kurt Cobain found dead, suspected suicide'. I thought I hadn't heard it right. It wasn't real. You know something's happened because rock stars never get mentioned on the news. On the journey, that was the only time my mum's boyfriend actually listened to Nirvana. He knew Kurt had died, so he let us play our tapes. But I wasn't really listening to the music, I was just listening to that radio headline over and over in my head.
"I think in a few years we'll see `Kurt Lives' graffiti everywhere. Lots of people at school already write it on their folders. I do."
What about in 10 or 20 years' time?
"Well, people are still crazy about Elvis, aren't they? You might get idiots dressing up as Kurt just like you get Elvis impersonators. I mean, I might do it even. Some people are copying him now. I put a rip in my jeans, across the knee, like him.
"Kurt did have a responsibility to his fans, though. He seemed like he had a weak character, but he was a good person. I still think it was brave of him to commit suicide, in a way. Having a wife and a child didn't stop him, so you can imagine the pressure he was under - it would have got anyone down. I feel sorry for his daughter the most. I couldn't cope with that if I were her and I grew up and found out all that about my dad."
Luke's adoration of Cobain is the unconditional kind that young people can afford. Michael, 23, is typical of the mixed emotions felt by older fans, caught with conflicting feelings of respect and anger.
"The more I think about it, the madder I get. If I'd had his money, I'd be made up. Money does buy happiness, it can get you freedom, which is more important than anything. And if he didn't like what he was doing, well he should have just jacked it in. He had that freedom and most people don't. He still would've had the money, and a family. It's not a difficult choice, is it? He was a brilliant musician and everything, but it was stupid for him to go and kill himself. Why would you want to kill yourself if you had that much money?"
What has Kurt Cobain bequeathed to his millions of fans? Some of the greatest music of the Nineties, a lot of ripped jeans, and even more questions about who he was and who they are, too.
IT'S BETTER TO BURN OUT THAN FADE AWAY
JIMI HENDRIX: The innovative blues guitarist died on 18 September 1970 after choking on his own vomit. His death remains a mystery. He was thought to have suffered depression after he had to support the Monkees. Reports of a suicide note are still hotly disputed.
JANIS JOPLIN: Years of drugs and alcohol abuse had savaged her body. The heroin overdose that killed her on 4 October 1970 was regarded as inevitable by many. Like Kurt Cobain, it was more a case of "when" rather than "if". Joplin was nearing completion of her final album, Pearl, at the time.
KEITH MOON: His wild-eyed clowning with the Who provided the perfect antidote to singer Roger Daltrey's on-stage preening and Pete Townshend's guitar heroics. Moon was an awesomely powerful drummer. He died on his 31st birthday, 23 August 1978, after overdosing on pills prescribed to treat alcoholism.
JIM MORRISON: Poetic genius and rock god to some, pretentious, overblown pseud to others. Morrison died in a bath in Paris from a heart attack, though his years of excess almost certainly played a role. Judging by the albums the remaining members of the Doors cobbled together, he jumped ship not a moment too soon.
ELVIS PRESLEY: The most famous case of rock'n'roll burn-out, now the butt of a million tasteless cheeseburgers-and-pills jokes. Presley's weight ballooned and his excessive use of barbiturates became almost as shocking as his vaudevillian dress sense. Official cause of death was heart attack, but no one was fooled.
SID VICIOUS: After a disastrous American tour the Sex Pistols self-combusted, and Sid freewheeled for a year before his death from a heroin overdose on 2 February 1979. He died while on bail after being charged with the murder of his girlfriend, Nancy Spungen, stabbed to death four months earlier.
HANK WILLIAMS: Seminal country musician. He had already lost jobs through alcoholism. Heading for a New Year's Day show in Ohio, Williams died in the back of a limousine from a heart attack brought on by drugs and alcohol. A traffic cop had stopped the limo earlier and remarked on Williams's cadaverous appearance.
BRIAN JONES: The Rolling Stones guitarist was found dead in his swimming pool on 3 July 1969. Two days later, Mick Jagger dedicated a poem by Shelley to Jones at a free concert in Hyde Park. Even the Hells Angels policing the crowd were touched.