Eamon McCann from Wonderland Promotions got the call from a SDLP official on the afternoon of Friday May 15. He learnt that U2 wanted to make a gesture, to endorse the Yes vote campaign for the Belfast Agreement. Any chance of fixing up a gig with say, four days to spare?

McCann was actually in London, taking time out to visit the tea room at Fortnum & Mason's. But he accepted the gig, sat down in the middle of the department store, and presently he had sorted out a venue and a date: The Waterfront Hall, Belfast, Tuesday, May 19th.

The team from Ash was installed in Rockfield Studios in Wales on the Friday night, mixing the band's second album. But again, there was no hesitation when the request came through. They'd definitely play. And yes, U2 could have a lend of their gear for the night.

What emerged was one of the defining moments of the election campaign. The Yes parties had been flailing after the appearance of convicted terrorists, grandstanding at the Sinn Fein and UDP rallies. Ian Paisley and the dissenters had assumed the moral high ground. But then music and young people came onto the agenda.

Suddenly there was a new, informed section of the electorate out there. People with their entire lives to bargain for. The absolute embodiment of hope – a group that had little respect for conservatism or the backwards look. When it was all over and the 71% vote came in, the media agreed that the the two gestures that swayed it were the personal pledges of Tony Blair and the Waterfront show.

U2 had wanted to avoid party politics, so it was an extra incentive for the SDLP and the Ulster Unionists to work together, promoting the Waterfront gig and distributing free tickets to sixth formers in their respective areas. The international media, who were in Belfast en masse, were thrilled at the opportunity to cover something a bit fresh and 'sexy'. It was a winning story from the off.

The Ash statement was sent out on the Monday. With blazing conviction, it stated: "We were born during the troubles and don't want to see outworn attitudes holding our country in the past. The people want a better future and are going to vote YES."

It was my job to read a more lengthy version of this message on stage at The Waterfront, at the start of the night. Walking out there and feeling the collective buzz of the crowd was the highpoint of this writer's career. Behind was a backdrop that read "Yes: Make Your Own History". In front were 2 000 euphoric young people, many of them reaching a stage in their lives when moving abroad is almost a routine decision. But everyone in that venue seemed to be re-comitting themselves to the place.

Given that both bands were rusty and had only managed to rehearse ten minutes before the gig, it was never going to be a technically great show. But the vibe was collossal, as Ash relayed their hits, interspersed with five new songs, which sounded wild and trashy in a Stooges kind of a way.

Bono and Edge came on for The Beatles tune, 'Don't Let Me Down'. Then Bono introduced David Trimble and John Hume, who shook hands, centre stage. It was an astonishing moment - another signal that the seemingly hopeless mould of Northern Ireland politics had fractured.

John Hume, bless his enormous heart, left the stage in tears. The U2 song 'One' has the ability to crack the binary code of every emotional moment. So it was in Belfast, as Bono hymned the joys of collective action, of rolling on in spite of the differences.

'Stand By Me' wrapped it up, a great piece of synchronicity, given that earlier in the day, David Trimble had told reporters that the pop gig he attended was by Ben E. King, the performer of that song.

Afterwards, you realised that rock and roll had engaged itself in a cultural event that had been largely neglected by sport, drama, fashion, painting, poetry - all of that stuff. Also, U2 had provided themselves as passionate emissaries and allies from the South, one of the few representatations outside of politics. All of this was reason to be proud.

David Trimble constantly referred to the show during the rest of the campaign. He talked about his 14-year-old daughter, and his expectations for her life, and the guy was visibly softening up. It was a tangible issue. It mattered.

Just after the show, the bands and their associates gathered backstage to watch the news on the television. And there it was, third story down, flagged by the image of Trimble, Hume and Bono, with their hands aloft, sending out an unmistakable signal.

"That's the shot," said Eamon McCann grinning. Larry Mullen walked in a few minutes later. "Did we make the news?" he asked. You did, surely.

What they said about the Waterfront Show...

THE EDGE:

"Like everyone, we'd been trying to figure out if there's something that we could have done. We didn't want to do anything that was party political; we wanted to involve both sides of the political spectrum. This idea came up. We heard that it was a possibility and we said, if you can get it together, we'll come and do a few songs.

"It was just amazing on stage. All the hairs on the back of the neck time. We were as ropey as fuck. We used Ash's gear. We didn't bring anything. I'd never played that guitar until we started, so it was interesting. But the vibe was what it was all about and the crowd just got it. They got the idea of the moment and they were so into it. That's what was exiting. That was my idea to play 'Don't Let Me Down'. A bit cheeky, but appropriate for the moment."

JOHN HUME:

"It was a wonderful night and very very moving. When you consider the audience were all totally young people, and they were all speaking with one voice. and the voice they were speaking with was the voice of Ash who said earlier today that their generation was a generation that had lived through all the troubles and therefore they wanted to leave all that behind them. It was very powerfully backed up by the total emotion of the entire audience. And I have no doubt that our young people from all sections of our community want to see a future on which the past that they have lived through is left behind. And we have a future in which they will all respect each other and work together."

BONO:

"I know John Hume a litle bit, and we were asked to help out with the Yes campaign, so I said if you can bring together John and David Trimble, we'll do something. I was very surprised when they both came back and said they wanted to do it, to be honest with you. We couldn't play a proper gig because our road crew had gone off, so Ash stepped in. They're a boss rock band, they're just on it. And I think that most importantly, the people needed to see these two men together. Forget us; we're up from the south and we wouldn't dare patronise people up here. but it was still nice to throw in our tuppence worth."

TIM WHEELER:

"It was a great day, really buzzing. As soon as we walked offstage, John Hume was standing there and he gave me this really big handshake. I think he was really quite moved by the event. I felt quite proud. My mum and dad were there and they said they were quite chuffed by what we had done.

"The result is brilliant - I'm dead chuffed. Paisley doesn't seem too impressed, as usual. He was saying that the Yes campaign had spent so many millions trying to buy people's votes, but I didn't see that at all. We all did it for free because we all believed in it. I remember just as Rick was leaving, I asked him what he thought of it, and he was stunned by the whole thing. John Hume and David Trimble together, it was quite crazy, really

"About seven o' clock, we were due to go on stage and U2 had just arrived, so we had about ten minutes to run through the songs that we were planning on doing. During the gig, we did 'Stand By Me' - we didn't even know we were doing that until Bono turned round and said, let's do one more - let's do 'Stand By Me'. He said to me, sing the first verse, and I couldn't remember it. The next day, I was kicking myself, I wish I had done it. But it was still a great buzz. It was great for rock and roll - it really stuck its neck out on the day."