Genocide perpetrators must be brought to book.

Last year, I visited Rwanda as United Nations Special Adviser of the Secretary-General on the Prevention of Genocide, to honour and pay respect to the victims and survivors of the genocide against the Tutsi in Rwanda. My visit was also aimed at contributing to advancing national reconciliation and trust-building efforts across the country, including by supporting initiatives at the local and community level.

Portrait of Ms. Alice Wairimu Nderitu

Ms. Alice Wairimu Nderitu, Under-Secretary-General and the United Nations Special Adviser of the Secretary-General on the Prevention of Genocide

This year as we mark, the anniversary and the beginning of the mourning period, Kwibuka, I remember too that Rwanda is a country of historical significance to my office. The mandate of my office was created largely because of the failures of the United Nations and the international community to prevent and respond to the genocide against the Tutsi in Rwanda in 1994 and the Srebrenica genocide in 1995.

Secretary-General Antonio Guterres often states that acknowledging the past is a vital step towards rebuilding trust, and that reconciliation means rejecting denial of genocide and war crimes and of any effort to glorify convicted war criminals. It also means recognizing the suffering of all victims and not attributing collective guilt.

The International Criminal Tribunal for Rwanda (ICTR) determined conclusively that a genocide was committed against the Tutsi in Rwanda. This constitutes an important step towards re-establishing peace and security in Rwanda and promoting reconciliation among Rwandans.

I came to Rwanda from an earlier visit to Bosnia and Herzegovina, where another genocide, the Srebrenica Genocide happened. My visit to Bosnia and Herzegovina was due to growing concerns around persistent patterns of denial of the crime of genocide, crimes against humanity and war crimes, glorification of war criminals, hate speech, and rhetoric of division.

There is a pattern to denial of not just the Srebrenica Genocide, but also the Rwandan Genocide against the Tutsi, and the Holocaust. Those who deny these atrocities also celebrate the criminals who committed these atrocity crimes. The arguments for denying all three of these most tragic of human experiences, genocide - the crime of crimes - are similar and without merit. The deniers ignore historical facts and judicial decisions.

Yet justice continues to be done. In Germany, a man in his 90s was recently...