Editor's note: Liu Cheng is a professor of history at Nanjing University and UNESCO Chair on Peace Studies. The article reflects the author's opinion and not necessarily those of CGTN

Perhaps the biggest trauma of every nation is the memory of a massacre.

For Europe, the brutal murder of six million Jews by the Nazis is perhaps the most indescribable deed. In China, the systematic extermination of 300,000 Nanjing citizens by Japanese soldiers in only six weeks of the occupation is one horrible piece of history of which the cruelty could never be "surpassed."

Each of the genocide in the history deserves a proper examination both by historians and common people. But this does mean that one should look at these tragedies separately in its own case, as it would prevent us from realizing that brutality like this is a general problem of humanity and conflict management.

A massacre is never a singular phenomenon; rather it is a general anthropological problem and therefore much more than an isolated and unique human catastrophe.

And if so, does the "common crime" shared by all human history make individuals and soldiers who held a gun in his hands less guilty?

The International Day of Commemoration in Memory of the Victims of the Holocaust on Sunday is an occasion to rethink a long-debated issue in many countries.

There has been a discussion as to whether or not a soldier who followed the order and committed the killing is a murderer in the traditional sense. From the perspective of Peace Studies, the ethical question cannot be answered easily by making a parallel between killing an individual – either for a particular personal interest or as part of a clear plan – and killing people in the context of a war.

Such a comparison would deny the complexity of what is happening in the war. People have long been wondering what happens in a war that makes a devoted husband or a loving father become a ruthless killing machine. But in a war, what's required from a soldier is to obey. They kill because of decisions of politicians and military, behind which there is a complicated framework of specific political socialization and education often in a context of ideology, propaganda, and indoctrination.

If they have spent 20 years of learning how Jews are inferior or how their own race is the most superior one, and now they are at the forefront of fighting for the existence of their own race, it almost seems reasonable for them to pull the trigger.

However, this doesn't mean in any sense that a soldier is not liable for what he has done legally. But an ethical judgment or the study of the massacre has to take into account the highly complex circumstances of war. It is not the simple, unsophisticated individual who should shoulder the main responsibility in ethical terms; it is the political and military elite, the intelligentsia of society and the representatives of the multi-societal organizations and facilities. They may not have blood in their hands, but they are the ones who have opened the floodgates of legal killing.

War bombarded cities as well as beliefs, also the base of a civilized world that's based on law and order. Once they have got the "license to kill," it is easy to imagine that they would steal, rob and rape and eventually be transformed into a killing monster.  

In that case, it is fortunate that today there are thousands of youth fighting for peace at the very forefront around the world. They are willing to pool their resources together and investing their energy to work for a more peaceful world. They are the future elites that will shoulder the responsibility of a world free from dangerous political games that could lead to war and tragedies. 

(Top image: Austrian President Alexander Van der Bellen (L) and the President of the Jewish community Israelitischen Kultusgemeinde(R) in Austria Oskar Deutsch take part in a wreath-laying ceremony to mark the 80th anniversary of Kristallnacht, in front of the Holocaust Memorial in Vienna, Austria November 9, 2018. /VCG Photo)

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