Over the years, I have travelled far and wide across Bosnia and Herzegovina and tried to be present at all the major events. This is, however, the first time I have attended the commemorative ceremony for our 12 colleagues who died here in pursuit of peace nine years ago.

I have not come to this ceremony or place before because for me, even now, the wounds of this tragedy remain fresh. Five who died in the tragic helicopter crash had been working for the Office of the High Representative, six for the UN Mission in Bosnia and Herzegovina and one, Peter Backes, for me in my role as International Mediator.

The 12 victims of this tragedy were all engaged in the painstaking task of helping piece Bosnia and Herzegovina back together after close to four years of war and were on their way to a series of meetings with representatives of local authorities. Peter was doing the preparatory work for my upcoming mediation trip that we had hoped to use to kickstart the returns process in Central Bosnia.

Every death is an individual tragedy and the pain of losing a loved one for the survivors – the friends and family – can never be underestimated. Even nine years on, I find it difficult to come to terms with the death of one so young, so gifted and with so much to live for.

It is impossible to generalise about the motivation of the many internationals who have come to work in Bosnia and Herzegovina over the years. However, especially those, like Peter, who spent time here both during the war and in its immediate aftermath shared a spirit of adventure and, above all, idealism.

They were committed to building peace in Bosnia and Herzegovina and determined that their contribution – whether to reconstruction, refugee return or the protection of human rights – would make a difference.

Looking back over the past decade, I am convinced that the individual contributions of many, many people have made a difference, that they have helped take the peace process forward and, above all, that they have helped provide hope of a better future.

I also wonder what Peter and the 11 other victims of the helicopter accident would make of today’s situation. I sincerely hope that they would take pride in the many genuine achievements of the peace process. But I suspect that, above all, they would be concerned about maintaining the momentum and ensuring that this peace process became genuinely self-sustaining.

Our gathering to honour the memory of Leah Melnick, Charles Morpeth, Thomas Reinhardt, Jurgen Schauf and Gerd Wagner from the OHR; of Livio Beccaccio, Andrzej Buler, David Kriskovich, William Nesbitt, Marvin Padgett and Georg Stiebler from UNMIBH; and of Peter Backes, is therefore also an occasion to renew our own commitment to peace in this country. That, after all, is the only appropriate tribute to these 12 fine, young people for the ultimate sacrifice they made.