There is no doubt that the Belfast or Good Friday Agreement, reached on 10 April 1998, was an achievement of historic magnitude. It was a day when politics triumphed over the devastation that had torn Northern Ireland apart since the outbreak of the troubles in the late 1960s. Tomorrow, I will join a number of figures involved in the Agreement to mark the 20th anniversary.

To put the Agreement in its proper context, it is worth recalling something of what Northern Ireland had been through in the two decades that preceded it. Over 3,500 men and women lost their lives, with thousands more maimed and injured. Terrorism was a daily fact of life, as was the security presence necessary to counter it....