I was brought up, in Apartheid South Africa, knowing that Nelson Mandela was a terrorist. No question, the church, the school principal, the Government said so. In fact Mandela said so too: in his address to the Court at his trial for treason in 1964 he justified the use of violence against property, but also the formation of a military wing due to the intransigence of the Apartheid Government.

Amnesty International never accepted Mandela as a prisoner of conscience, due to his refusal to renounce violence as a means of political change.

The Christchurch shooter referred to Mandela in his manifesto. Many similar terrorists claimed that terrorism was their only recourse, as they had no other way to express their political aspirations. Yet the Christchurch shooter, along with the authors in most acts of terror, all have access to sophisticated democracies, however imperfect these may be.

And there lies my imperfect personal definition: terror as means of political change or expression can only be justified once all other ways of bringing about change have been exhausted. Daesh may have claimed imperfect political structures in Syria. Israel, in denying an effective democratic voice to many, runs the risk of terror. Sudan is experiencing a growing popular uprising against an ossified, hard-of-hearing Government, who has denounced many activists as terrorists. Algeria is in the grips of a similar change.

But back to my story. In my years of Government work I learned much about Mandela and the ANC, and heard whispers that, behind Mandela, there was a worse terrorist: Raymond Mhlaba, the first ANC leader to guide the military wing from exile. Secretary General of the South African Communist Party.

In 1990 I watched Mandela walk free, after an intricate and as yet not fully told process. It was my privilege to meet him several times, and found him a warm, gentle and sincere person, dedicated to building the ‘Rainbow nation.’ And in 1997 I was asked to act as Deputy to the South African High Commissioner to Uganda, Mr Raymond Mhlaba.

I worked with “Oom (uncle) Ray,’ as he was known, for four years, a kind, considerate and humble man. But what remains with me was his account of the process that ended the civil war. Mandela had analysed the political situation in and around South Africa, and had decided to take the risk of opening negotiations with his enemies. “If you want to make peace with your enemy, you have to work with your enemy. Then he becomes your partner.”

Most leaders today seem to seek division and to set groups and labelled peoples apart. Their enemies seem to define them as leaders. Few are the real leaders who seek to build bridges.