A conference in the Canadian city of Montreal has been discussing ways to prevent genocide. BBC world affairs correspondent Mark Doyle, attending the meeting, asks whether this can be done.
The 75-year-old woman sat on stage in front of hundreds of United Nations officials, legal experts and academics.
Some 800,000 Rwandans were slaughtered in 100 days in 1994
The day before, Marika Nene had travelled from Hungary to Canada - the first plane she had ever taken on her first journey outside Hungary.
She was not intimidated by the gathering. Her long hair was lit up by a stage light and her facial features were strong.
But the strongest thing about Marika Nene, a Roma - or Gypsy - woman who was trapped in the anti-Gypsy pogroms during World War II, was her determination to tell her story.
"I had no choice. I had to give myself up to the soldiers," Marika Nene said through a translator.
"I was a very pretty little gypsy woman and of course the soldiers took me very often to the room with a bed in it where they violated me. I still have nightmares about it".
Many members of Marika Nene's Roma family died in the work camps and the ghettos.
She had travelled to Montreal to give a reality check to the experts and UN officials at the "Global Conference on the Prevention of Genocide".
She was joined by other survivors - from Rwanda, Cambodia and the Jewish holocaust. They all told their horrific stories bravely.
But there was something especially extraordinary about the elderly Roma who had transported herself from a village in eastern Hungary into the glare of an international conference in one of the most modern cities in the world.
It was an example of what Nigerian Nobel Prize-winning author Wole Soyinka would later describe to me as one of those points where people meet each other in a spirit of "egalitarian awareness".
Six million Jews or one million Tutsis are just numbers. But this strong Roma woman was a human being who was not ashamed to tell her story.
The Montreal conference drew personalities from the UN, academia and the legal profession.
The general aim was to build pressure on politicians to take mass killings - even in far-off places about which we know little and sometimes care less - far more seriously.
Romeo Dallaire could do little to prevent the Rwandan genocide
If that sounds like a fuzzy and vague ambition, Canadian Gen Romeo Dallaire, who commanded a UN peacekeeping force in Rwanda during the 1994 genocide, begged to differ.
Gen Dallaire led a force in Rwanda which was betrayed by UN headquarters in New York - his mission was starved of resources and so forced to observe genocide rather than stop it.
Since that failed mission, he has made a career out of lobbying politicians to do better on issues like peacekeeping, abolishing the use of child soldiers and nuclear disarmament.
"This conference is aimed especially at young people," said Gen Dallaire from a hotel surrounded by the campus buildings of McGill University, which organised the conference.
"If these young people became politically active," he continued, "they could dictate a whole new concept of what national interest should be and what humanity should be."
What is genocide?
Payam Akhavan, professor of international law at McGill and a former prosecutor at the UN war crimes tribunals for the former Yugoslavia and Rwanda, said defining genocide mattered from a legal point of view - but that analysing how it could be prevented was the real point.
"The legal definition of genocide is contained in the 1948 Genocide convention," he told me.
Pol Pot, who led Cambodia's Khmer Rouge, was never brought to justice
"In simple terms, it is the intentional, collective destruction of an entire human group based on national, racial, religious or ethnic identity."
"But the key point", Mr Akhavan continued, "is that we do not need to have a legal finding that genocide has been committed in order to take preventive action."
That is because, of course, by the time the lawyers have decided a mass killing fits their definition, it is usually too late to act.
The Iranian-born professor said it was necessary to think about the ingredients of genocide, which he listed as:
- incitement to ethnic hatred
- demonisation of the target group
- radicalisation along ethnic or religious lines
- distribution of weapons to extremist groups
- preparation of lists of those to be exterminated
As someone who personally witnessed and reported on the Rwandan genocide, I found it quite disturbing to read about other mass killings.
It was not the details which I found shocking, but the spooky similarities that kept cropping up across the world.
The lists prepared by the Hutu extremists in Rwanda, for example, were mirrored by the obsessive recording of the details of victims by the Khmer Rouge in Cambodia.
The yellow identity stars Jews were forced to wear in World War II were the equivalent of the ethnic identity cards every Rwandan had to carry.
This is the grim opposite of Wole Soyinka's "egalitarian awareness". It is the social science of genocide, which appears to have common features across history.
The conference aimed to isolate and analyse Mr Akhavan's "early warning" factors to raise awareness.
But what to do with the information?
As speaker after speaker reminded the Montreal conference, the US government, among others, has asserted that genocide is being committed right now in the Darfur region of Sudan.
It was continuing even as we sipped our coffee in softly carpeted rooms and nibbled our Canadian canapes.
Everyone has known about it for several years but virtually nothing had been done to stop it.
A dissident voice
So all the talk about "early warnings" and "United Nations peacekeeping forces" and "the will of the international community" could be said to amount to little.
At this point, a controversial scholar intervened with comments which challenged the entire conference.
The US and others have said a genocide is unfolding in Darfur
French author Gerard Prunier, like the proverbial ghost at a wedding, said genocides could not be prevented by the international community.
"When you see a dictatorial regime heating up, everyone starts talking, talking, talking ... and by the time the talking stops, either matters have quietened down or they have happened."
And that is the crux of the matter, according to Mr Prunier - it is difficult for politicians or the military to intervene in a situation that has not yet evolved into a crisis.
Give war a chance?
So what is Mr Prunier's solution?
"Genocides can only be stopped by the people directly involved - and usually that means people involved in the war that accompanies most mass killings."
And if it is the government committing the genocide, the solution is "arm the rebels", he says.
"It won't be clean - it will be messy," the French author said, "but it is more likely to stop the mass killing than international intervention."
To a large extent, Mr Prunier has history on his side. The Holocaust only ended when the allies destroyed Hitler's regime.
The killing fields of Cambodia's Khmer Rouge were only stopped when the Vietnamese army moved in. And the genocide in Rwanda only ended when the Tutsi rebels overthrew the extremist Hutu regime.
Against this, it could be argued that some interventions have worked - for example the Nigerian intervention in Liberia, which was followed up by a UN peacekeeping mission.
It seems that resolving dramatic human rights abuses may require some of the diplomacy and the "international good will" that flowed so freely in Montreal.
But as well as what Winston Churchill called "Jaw Jaw", some situations, it seems, may only be resolved by "War War".