The Rohingya crisis in Myanmar, which the United Nations high commissioner for human rights has called a “textbook example of ethnic cleansing,” highlights a problem that the world has not yet figured out how to solve — and that can contribute, in extremes, to the world’s worst atrocities.

National self-determination, the idea that a nation should have the right to freely choose its political status, is a central tenet of the international system. It is enshrined in Article 1 of the UN Charter, which states that its purpose is “to develop friendly relations among nations based on respect for the principle of equal rights and self-determination of peoples”.

But scholars have long recognised that there is a problem inherent in self-determination that can make it an enemy of the freedoms it is intended to protect. Self-determination means not only defining what a nation is, but also who belongs in that nation and who is an outsider.

During times of political upheaval, when national identity comes under pressure and different groups compete for claims to self-determination, such definitions can provide an impetus for mass violence and even genocide against those deemed to be outsiders. It is easy enough to define a “state” — a place with borders, territory and a sovereign government.

But a “nation” is a hazier concept — a group of people bound together by some common characteristic, which may or may not match up precisely with state borders. That is where things get tricky.

Most countries have a majority ethnic or religious group whose customs, culture and religion dominate public life. But ethnic or religious definitions of the “nation”, when translated into political priorities, put minority citizens at a disadvantage.

If the majority group wins self-determination, the resulting state will not be designed to represent minorities, even if they technically have full citizenship.

That kind of definition can also create stress for the majority group. Kate Cronin-Furman, a fellow at the Belfer Centre for Science and International Affairs at Harvard’s Kennedy School of Government who studies mass atrocities, said that when nations are defined around a majority ethnic group, that can lead to a sense of siege — a belief that majority status needs to be protected, because if it shrinks, the claim of the majority on the nation could as well.

In Sri Lanka, for instance, the Sinhalese majority has defined the nation as Sinhalese and Buddhist. As a result, Ms Cronin-Furman said, Sinhalese political rhetoric is consumed with the idea that any expansion of rights to non-Sinhalese citizens is a threat to the nature of the state.

Civic nationalism, which is based around citizenship and shared political beliefs rather than ethnicity, is more inclusive. But that same inclusivity can make it challenging to create a strong, cohesive sense of national identity. When that happens, focusing on outsiders — identifying who is not part of the nation, rather than who is — can seem an expedient short cut.

Political psychology researchers have long found that when leaders cast outsiders as different and threatening, that can strengthen insiders’ sense of identity and group cohesion. But that can leave minorities at risk of discrimination or even violence.

At times of stress from factors like war, major political changes or economic collapse, competition over who is entitled to national self-determination can trigger extreme violence.

Professor Stefan Wolff, a political scientist at the University of Birmingham in England who studies ethnic conflict, has found that many of the world’s worst conflicts have arisen when ethnic and political borders do not line up with one another. “From Kosovo to Silesia,” he wrote in a 2004 article, “the competing claims of distinct ethnic groups to self-determination have been the most prominent sources of conflicts within and across state boundaries.”

When states collapse or state borders are withdrawn, he has found, that creates an opportunity for groups to establish their claims to national self-determination. And when multiple groups lay claim to nationhood within the same territory, “ethnic cleansing” can come to seem like a grim but effective solution, a way to make ethnic and national borders line up by forcing out members of competing groups.

When the former Yugoslavia collapsed, for instance, Bosnian Serb forces committed atrocities against ethnic Bosniaks and Croats as part of their effort to establish a Serbian Republic.

In Myanmar, the Rohingya have long been demonised as outsiders in their own country. They have been present in Myanmar since the 12th century, according to Human Rights Watch. But excluding them from the nation, and later even from legal citizenship, has long been a political tool, part of the process of defining the nation by deeming some outside it.

After British rule ended in Myanmar — then Burma — in 1948, the new government argued that the Rohingya were illegal migrants from British-administered India, now Bangladesh, not truly part of the new nation. A 1982 citizenship law effectively stripped many Rohingya of citizenship, deeming them foreigners in their own country.

In 2015, the government disenfranchised the Rohingya en masse, preventing hundreds of thousands from voting in national elections.

And in recent years, politicians, including the democratically elected leader Aung San Suu Kyi, have implied that they were terrorists who threaten the nation.

Today, civilian politicians and the military are jostling for control as the country moves towards democracy. Laying claim to national identity is a way to lay claim to power. And once again, that has had tragic consequences for the Rohingya.

In a Facebook post on Saturday, Gen Min Aung Hlaing, head of the armed forces, tried to justify the army’s attacks on the Rohingya by saying it “has never been an ethnic group in Myanmar”, and claiming that the mass violence that had displaced so many was “an organised attempt of extremist Bengalis in Rakhine state.”

Independent observers say the army has burned Rohingya villages and targeted civilians in a campaign of rape and slaughter.

National self-determination is not a licence for attacks against minorities. But by emphasising that right, the international community may, however unintentionally, have seemed to offer an implicit incentive for the catastrophe now playing out in Myanmar. THE NEW YORK TIMES

ABOUT THE AUTHOR:

Amanda Taub is a writer for The New York Times Interpreter, which explores the ideas and context behind major world events.