Former prime minister Tony Blair, who along with Irish premier Bertie Ahern led the peace talks in Northern Ireland, said the Good Friday Agreement gave hope to conflicts across the world.
15 years ago, when I came to Stormont, there was little expectation of a deal being done. The peace process was in turmoil. But because of the will of the people in Northern Ireland, that historic Good Friday signalled the start of a peaceful future.
Now as I travel to different parts of the world, what happened in Northern Ireland is something that immediately connects with people. It brings hope for other conflicts - from Africa to the Middle East - that a situation that once seemed so bleak can be resolved.
There will be political crises, and there will be continuing problems, but I firmly believe that Northern Ireland will not return to the times of the Troubles. The gains of peace are visible and clear, and there is an overwhelming desire from the people for this to remain.
So 15 years on, we should remember the past but also look confidently towards a peaceful future for Northern Ireland. There can be no going back
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