Exactly a year ago, Jason Russell was a nobody. Not a nobody, precisely, but just ordinary. Normal. He was a healthy father of two, living in San Diego, and was happy and fulfilled in his work as a director for Invisible Children, a non-profit organisation he'd helped found.

And then, on 5 March, he released Kony2012, a 30-minute film that explained why the world needed to catch and bring to justice Joseph Kony, a central African warlord, who, over the previous 26 years, had abducted 30,000 children and turned them into soldiers and sex slaves. Russell directed and starred in the film, and within hours it was on its way to becoming what was then the most viral video of all time. It took a day to hit a million views; six days to reach 100 million.

Every news outlet on the planet, it seemed, wanted an interview with him. Every news website in the world carried a story on him. Every blogger had an opinion on him. More than a million people left a comment about it on Youtube. On Facebook, 11 million people clicked on "share".

Ten days later, he ripped his clothes off his back, ran out naked into the street near his San Diego home, slammed his hands repeatedly on to the pavement, battered himself against parked cars, and screamed obscenities until he was eventually led away by police. This, too, became a viral video.

His doctors never agreed on a definitive diagnosis but he was sectioned in a psychiatric hospital suffering from what may have been a schizophrenic manic episode brought on by post-traumatic stress. It was nearly two months before he went home to his family. He is still on "mood-stabilising" medication.

Kony2012 was both ubiquitous and, for all sorts of reasons, extraordinary: it wasn't a two-minute video of a cat falling into a toilet or a baby laughing. It was about an obscure region far away and the importance of pursuing international justice. And Jason Russell.

And it provoked an extraordinary response.

"The only way a video could get more viral is if Susan Boyle and the Cat Bin Lady teamed up to eat shit out of one cup," said Charlie Brooker. "It looks like a T-Mobile advertisement shot by the Pepsi Max pricks… with a charismatic front man who looks like an Abercrombie & Fitch version of Jesus Christ."

And this was probably one of the more moderate views. A year on, the Abercrombie & Fitch version of Jesus Christ is looking tanned and healthy in his office in San Diego, but he eyes me with a certain wariness. Last autumn, he went on Oprah Winfrey's show and NBC's Today show and spoke about what happened to him, but not in this detail, at this length.

"On the one hand, there was Bono saying Jason Russell deserves an Oscar, and Oprah wants to fill stadiums for me, and Ryan Seacrest wants me on American Idol," he says. "And on the other, there were people saying, 'These people think they're white saviours trying to save Africa', and 'the money goes to corrupt places', and 'there is a special place in hell for you'.

"They were so polar opposite. So extreme. And in my head, I wanted to reconcile them and I just couldn't."

For a week, he did interview after interview and it was only when he was in the office of a crisis management agency in New York, days in, he says, that he first realised the true force of the backlash. "My head was spinning with all this stuff we needed to do in the future. And Ben [Keesey, Invisible Children's CEO], was saying: 'No, Jason. We've got to work out what to do about the negative press.'

"And it was only then that I realised what was happening, when I opened up my laptop and the first article I read was all these terrible things. 'Jason Russell … white saviour complex…military intervention … dubious finances … blond … yadda yadda yadda!' And suddenly it was, wham, and I was right back in junior high."



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Russell's parents founded a national organisation called Christian Youth Theatre, and he spent his childhood as "the tin man, Mr Toad, Peter Pan". He loved musical theatre and his best friend was a girl, Danica, whom he met aged seven and went on to marry. And for all these reasons, he found himself bullied at school. "You think you're an adult and you're past such things and it turns out you're not. You can be taken back there in an instant."

In 2003, at the age of 24, after graduating in film school at USC in Los Angeles, he travelled with two friends to Uganda to find a subject to make a film about. In the town of Gulu they discovered thousands of children who spent every night sleeping en masse in the streets because of their fear of being abducted and drafted into Kony's Lord's Resistance Army (LRA). Their response was to form a charity called Invisible Children, for whom he has worked ever since, with the aim of trying to bring Kony to justice.

Nothing in Jason Russell's life had prepared him for the sharp end of the internet. "I'm a 'glass half full or overflowing' kind of person," he says at one point in our interview. "I've never been depressed. They thought it might be bipolar but my wife and my mom were like, 'That's just not you.' I don't get down."

He'd never experienced any form of mental illness. Or at least, he hadn't until the world wide web turned its hell dogs upon him. Could anyone have withstood the pressure that Russell was under? "My doctors say there are very few people who have been that unknown, and then that famous and who are then ripped to shreds."

When I ask him if he's processed what happened to him, and what effect it's had on his life, he says: "I don't know if I have processed it. I still … there are days when I think, 'That was a total failure.' That it was the worst thing that could have happened. That I let everybody down. And there are others when I think we did what we wanted to do. We set out to make Joseph Kony known. And now he is. So I can't… But the problem is that my breakdown put such a blanket of fear and distrust and shame over everything. That's something I deal with every day."

Or as Vice magazine reported it: "Those who live by slick viral videos can die by them too." A few days previously it had cautioned its readers not to give money to Invisible Children, because of its "dubious finances" and "exaggerated claims", adding that it was "staffed by douchebags".

Joseph Kony, leader of the Lord’s Resistance Army, which has forced thousands of children to become soldiers in Uganda and Congo

If Russell had had a heart attack, a coronary brought on by extreme stress, it might well be a different story. Heart-attack victims receive sympathy. People who rip their clothes off in the street don't, though attacking your own body is every bit as much of a symptom as chest pain. It's a measure of the stigma and acute misunderstanding that still afflicts sufferers of mental illness that his breakdown was, for many, some sort of vindication. They thought he was a douchebag. And this seemed to prove it.

"It was just so public," says Russell. "The visual of the video is so compelling. It's so obvious that I'm not OK. And I'm so naked. And it's just very, very public. The joke we always had, even before this happened, is that the internet is forever. If you put your crotch on there, it's for ever. And now this is out there for ever and my kids are going to have to deal with it at high school.

"The thing that sucks the most is that it gives people an excuse not to do anything. People are like, 'Didn't that film-maker take all the money and then go crazy naked in the street?'"

Russell didn't embezzle any money. Invisible Children has five years' worth of audited accounts and received four out of four stars for its financial health from Charity Navigator, a non-profit watchdog. "It spends upwards of 80% of its budget on its programmes and services," says Charity Navigator, "outperforming most charities in our database in terms of how it allocates its expenses."

It notes that some people "mistakenly" concluded from its data that it "did not complete an annual audit. That is not true."

Too late. It's just one of the fallouts of becoming a mega-trending Twitter hashtag.

When I visited Invisible Children's San Diego office last week, there were 60 staff members and 35 fresh-faced interns answering phones and plugged into computers in a cool, calm space. A year ago, says Chris Carver, the chief operations officer, it was another story.

"We had one PR person, Monica, who was an intern, a volunteer. She estimated there were never less than 4,000 emails in her inbox. In any one second, our website had 37,000 unique users. And we were taking hundreds of thousands of dollars of orders in our shop for the Kony2012 kits."

These were the "action kits" that viewers of the video were urged to buy to raise awareness of Kony.

"Even though we knew we might never have this opportunity again, we had to shut it off. We had two people in our fulfilment department, and they could ramp up to maybe 100 orders a day. And we literally had hundreds of thousands of them."

The kit included a red T-shirt with the words Kony2012 on it, but incredibly, "we maxed out," says Carver. What do you mean, I ask. "We sourced every single red T-shirt in the entire US. There were no more to buy."

The website had been stress-tested to cope with an Oprah appearance a year or so previously, but it crashed. The phone system crashed. "The only way we could communicate with the outside world was a Tumblr site so all the stuff about our financials, our five years of audited accounts, the detail of our programmes, the 11 schools we have built, the thousands of scholarships we have paid for, the early warning radio system we have built, none of that was up there.

"People wanted answers, they needed context. We had nine years' worth of it. We just couldn't get it to them."

You can stress test a website. You can't stress test a person. There's footage in a film Invisible Children released last autumn of Russell shortly before his breakdown. It's late at night. He's just got in from New York and he's visibly upset. "There's never been a war like this online ever," he says in the footage. "This is what they do to you. My anxiety … my fear is that it's all in my head."

"I wanted it," he says later in the footage. "I just didn't know what it would feel like." And he starts to cry.

The details of what happened next are pretty terrifying.

"I hadn't slept," he tells me. "My mind was racing. I tried to relax and calm down. They said, 'Take two days off', so we [his family] went to Palm Springs. But we went to the pool and people recognised us and wanted to take photographs so we went and shut ourselves in the hotel room, closed all the windows and the doors, and just felt we were under attack.

"The next day was a bit better, we went out to see a movie, The Lorax, a Dr Seuss film. And I thought it was talking directly to me. I thought it was all about me. The character is wearing a stripy top like the one [his son] Gavin is wearing in the film and I was like, 'That's so weird!' And the character is trying to protect these trees, and I thought it was me, and the trees were Rwandans."

Back at home, Danica had realised something was very wrong and had surreptitiously started to research symptoms on the internet.

"But I called up this friend, Bobby, and he came round and I said to him that I wanted him to line up all the books on my shelf and make sense of them chronologically so that we could determine the future of humanity. That's where my brain was. I thought we'd analyse the books and we'd come up with the answer of what the world needs to do next. I thought I'm the one who's going to help put it all together.

"And then it was shortly after that I heard the voice." The voice told him that he had to get to New York in 12 hours or Joseph Kony would win. "And it said everyone who had tried to bring peace to the world has had to pass this test."

And then he took off his clothes and ran out in to the street. He can only remember "slivers" of what happened next. The horror on his mother's face when he was handcuffed and led away – Danica had rushed out of the house with the children and called his parents. He was taken to hospital. "But I thought the staff wanted to kill me. I was convinced. They kept trying to give me drugs and I refused to take them. It got to the point where I was running around in my underwear kicking in doors. I had eight people holding me down. They eventually tied my arms and legs down to this bed and injected me. It was incredibly traumatising. I was convinced I was going to die."

He's so open about all this. "My publicist and the team, they say, 'Don't use words like schizophrenic, you'll get labelled for life.' But I'm like, 'I can only be myself. I might as well get it out there.'" At the height of the criticism, he was accused of running a cult, of embezzling funds, of running a covert evangelical mission. He was a narcissist, a megalomaniac, a racist war-mongering blowhard suffering from what one Twitter commentator called part of the "white saviour industrial complex".

Yet what's most apparent on meeting Russell is an almost complete lack of guile. He spills his guts for hours and then right at the end, he says: "You're not going to turn this round and make this all about my spirituality and the fact that I'm a Christian, are you?" At the height of the maelstrom, he took a call from a journalist and spoke to him for an hour and a half between 4 and 5.30am. "And then he wrote this awful 'exposé' for the Atlantic about how we were an evangelical cult. I'm incredibly open, it's just who I am, but I'm not sure I could handle being hurt and vulnerable like that again."

And yet he has invited me into the office (after six months' worth of emails, it's true), and shows me things that if I was a different sort of journalist I could so easily manipulate and exploit. There is an artlessness and innocence about him, still, even after everything that has happened.

One of the most striking moments in Kony2012 is footage from the 2003 trip to Uganda, when Russell and his two friends discovered thousands of children sleeping in the streets out of fear of being abducted and turned into child soldiers or sex slaves.

"And this has been going on for how long?" says one of them. "If this happened for even one night in America, it would be on the cover of Newsweek magazine!" You can feel their self-absorbed, righteous teenage outrage at suddenly realising that the world is fundamentally unjust and unfair, and it's this sense of outrage that somehow they have managed to keep hold of and harness.

There are all sorts of interesting technical and other explanations to why and how Kony2012 went viral, but it's perhaps not a coincidence that its popularity was propelled by teenagers. Teenage logic and outrage, in the very best sense, is at the heart of everything they do.

"We believe it's what pushes the needle forward," says Jedidiah Jenkins, Invisible Children's in-house attorney and director of ideology. "We know how the world works but we are saying, it's not OK. We practise 'intentional naiveté'."

It's so not OK that when Jacob, a Ugandan boy, describes in Kony2012 how he saw his brother being macheted by the LRA, Jason's voice can be heard telling him that he promises him he will try to do everything he can to help.

"It's the third film we'd put Jacob in," says Russell. "And we'd never included the bit about the promise before. It's so presumptuous. 'We're going to help you! We're going to try and stop him!' But we included it then because that is what we had been trying to do for nine years." They have. Most people would have quietly dropped it and gone back to their lives at some point. They didn't.

They thought that it would be enough to make the film and show the world what was happening, but it wasn't. So they went on the road and showed it to schools, and have been doing that ever since – 14,000 of them across the United States. Kony2012 wasn't just a video with slick visuals and a pop video aesthetic. There was almost a decade of direct face-to-face engagement behind it. And it was in places where they already had a network of supporters in place that the film first went viral. An overnight success just nine years in the making.

"There's nothing more powerful than an idea whose time has come," says Russell's voiceover at the start of Kony2012. Whatever you think of Russell, Invisible Children, or the rights and wrong of the kind of advocacy work they do, it's hard to deny the arresting brilliance of the video's opening sequence – even if you hated it, and many people did. Over a spinning planet, and spectral music, Russell explains that there "are more people on Facebook than there were on the planet 200 years ago".

Humanity's greatest desire is to connect, he says and "this connection is going to change the world". The video is a social media "experiment" to see if they can make Kony famous. And thereby show that, in this globalised world, nobody can escape the long arm of international justice.

Or, as a writer in Vice put it: "It reminded me of a manipulative technology advert of the Kings of Leon video where they party with black families. I mean, watch the first four seconds of this again. It's pompous twaddle with no relevance to fucking anything."

In what, depending on your view is either genius storytelling, or vomit-inducing self-indulgence, Russell has footage of his own son, Gavin, being born ("everybody on the planet starts this way"). And then has Gavin, now aged five, and ridiculously, photogenically cute, hearing about what Joseph Kony does to young boys not much older than him.

Russell is a southern Californian born and bred. He "dudes", he "mans", even at the height of his mental disintegration, he still sounded like an off-duty surfer. "It's just so… gnarly," he tells the team in the footage from that time. For a certain kind of website, the kind whose stock-in trade is snark, he was cannon fodder.

What was some blond Californian dude think he was doing telling the world about a central African warlord? A couple of days in, ridiculous photos of him surfaced: one of him and his team posing with guns. A video of them dancing that would make even the cast of Glee blush.

And yet, going to southern California to meet Jason Russell, it's possibly this that impresses itself on me most of all. The sun is shining, the Pacific ocean is sparkling, there is fine artisanal fair-trade organic coffee to drink just steps away, and yet all these fresh-faced shiny people are spending their days worrying about a conflict so far removed from their own lives that it seems farcical. Or at the very least heroic. They not only care, they have achieved what is supposed to be impossible: they have made other people, ordinary Americans, care.

Not only that, the University of California is carrying out a survey on a sample of the thousands of teenagers who have supported Invisible Children and has found that their engagement spreads to other issues and other parts of their lives. They are more likely to care about social issues, generally.

Here they were, as one website, Wronging Rights, put it in a widely repeated criticism, "taking up rhetorical space that could be used to develop more intelligent advocacy".

And yet seven months ago, while I was researching another story about central Africa – the tale of David Simpson, the Briton charged with a massacre that was actually carried out by Kony's forces – I spoke to the leading experts in the region. And, having read the coverage of Kony2012, the debate about Invisible Children's methods, the criticism of their simplistic approach, what surprised me was how the development professionals working closest to the ground in central Africa were full of praise for what they'd achieved.

Anneke Van Woudenberg, for example, from Human Rights Watch, said that they'd been "astounded" by the popularity of the video. "Whatever one thought of it, it massively, massively raised awareness of Kony. And awareness is step one in pushing for policy change. We found so much more interest from a whole range of policymakers. I've been working in central Africa for 13 years. I've been documenting LRA atrocities since 2006 and Human Rights Watch has been doing it since the late 1990s. There have been peaks and troughs but we have never seen the kind of interest that Kony2012 created.

"It was very very exciting. There has been so much engagement from the UN. They've passed resolutions. The US was the audience for the video and they've said they will keep their field advisers here, which was by no means clear before. The time limit has been lifted.

"There's still a long way to go but the criticism of the video, which was so scathing and vitriolic and which focused on Invisible Children, has just completely missed the point. Kony is still out there but the implementation of UN strategy is the thing that will make a difference. And it achieved that."

And then there was Mark Galloway of International Broadcasting Trust, which published a report on the impact of Kony2012 and held a symposium on it, and whose conclusion was "that the way in which charities communicate has to change in the wake of it". It was, he said, a "game changer", "for all of us to hear about it from our kids. That's how I heard about it, from my teenage son, 48 hours in. I was like, 'How come you have heard about a Kony video and I haven't and it's my job? And I haven't ever heard you talk about Africa before.'

"They reached young people in a way no charity has been able to do before. They connected to people's stories. It wasn't snazzy or trendy. It was just good old-fashioned story-telling."

Jason Russell and his son Gavin in a still from Kony2012, which was watched 100m times in less than a week last year.

You would never know any of this, however, from trawling the web. Before his breakdown, Russell says he was just inundated by "noise, chaotic, non-stop, constant noise". And it's all still out there. A Canadian girl of Ugandan descent uploaded a video film of her response to Kony2012 in which she says she told her parents about Joseph Kony and they said: "He's been dead for years!"

"It's had 6 million views and what? Maybe 3 million believed it," says Jason Russell with a look of pain on his face. "That lie permeated and it's still alive today and people on their campus or whatever are like, 'He's dead, he died so long ago.' And everyone in the room goes, 'I didn't know that!' The democratisation of information is both liberating and beautiful and also totally horrifying because it can be built on lies and there's nothing you can do to stop them.

"This is a generation raised on an Instagram and a tweet. That's your news. That's your actual news."

There is a frightening lesson at the heart of the story of what happened in Kony2012. It wasn't that there was a plurality of stories out there. There was a multiverse of stories out there. There were so many stories, so many rumours, so many repeated untruths, so many unchecked facts and retweeted opinions, and half-baked half-lies, that the story, let alone the truth, never had a chance.

In the brave new world of viral media, and socially mediated information, authoritative news sources are just another voice fighting to be heard. And half the time, even their stories were simply web-based trawls. It's like dredge fishing. You scoop all the crap up in one big net, including the bottom feeders and the plankton.

And then it's gone. In a puff of smoke. Look at Google Trends' graph that shows the distribution of searches for the word "Kony" and it goes from zero to 100 in a day, and now it's back down to one again. Jason Russell's breakdown stopped it dead in its tracks. The news moved on. Nobody cared what the truth was any more. This article is one of very few attempts to revisit the story.

"Young people are still convinced that we steal money," says Invisible Children's Jenkins. "They don't feel the white man's burden issue. Or the international intervention issue. They think they got scammed. That's out there now, for ever. It's just so weird to spend your life doing what you believe is worthwhile work and everyone in the world is out there trying to find dirt to make you look like a criminal."

Before Kony2012, Jason Russell says, "I was under the impression that I could will people's opinions to the truth and to what was right. I thought if we did a good enough job, said the right thing, made the right video, did the right interview, people would understand the truth."

And was it a hard lesson to learn that the world simply doesn't work like that?

"It's what made me manic," he says simply.

There are theses to be written on Kony2012. History will parse its meaning and effect. Which is a fancy way of saying time will tell. Perhaps. In his office, with its quotes from Steve Jobs on the walls, and his old scrapbooks and journals on the shelves, and its framed Time magazine with "Hunting Joseph Kony" on the cover, Jason Russell still veers between overconfidence and a sense of abject failure.

On the one hand, they succeeded: Kony really is pretty famous now. On the other hand, he's still out there. What do you say when people say you've failed, I ask him.

"We have failed. And we should feel like a failure until we get him. We've rebuilt schools and funded scholarships and inspired kids here but our number one goal has not been achieved and it is achievable. It's only one man. He now has only 200 fighters, three commanders. We have put a man on the moon. We can do this.

"We want to see him on trial. To prove that whoever you are, wherever you are, you can't get away with it. And this is what we are authentically trying to do. People think, 'Oh they want fame. They want money.' And it's sad that that's the way the world works. But come and meet us. We are not the villains you paint us on your trollblogs. We are genuinely trying to stop a madman from slaughtering children. That's it. That's the whole point of everything.

"What are you doing?"