News — All nations agree that terrorism is a scourge that must be fought, but United Nations member states have yet to agree on a clear definition of what constitutes terrorism—and that's despite nearly 50 years of ongoing debate. Why is a universal definition so elusive?

This is what Corentin Sire explores in his PhD thesis, which he wrote under the co-supervision of Professor from the Université de Montréal's School of Criminology and Professor Thomas Hippler from the Université de Caen Normandie in France. His research findings were published in the journal .

Sire first started researching the topic in 2016, a time when concerns about terrorism were running high. He learned that the term emerged in 18th-century France. "It was originally used to retrospectively describe—and condemn—the Reign of Terror that occurred during the French Revolution," Sire explained. "And like any insult, its definition is fundamentally subjective."

A history that dates back to the inter-war period

According to the literature reviewed by Sire, the concept of terrorism first appeared in international law at the 1919 Paris Conference, where the term "systematic terrorism" was associated with war crimes against civilians.

"But the League of Nations (the organization that preceded the United Nations) only began to give the topic more serious consideration after the attack on Marseille in 1934," he explained. "A definition of terrorism was finally included in two international conventions, but the documents never came into force because they were shelved when the Second World War broke out."

Even after WW2 ended, the UN didn't revisit the concept for nearly 30 years. The issue resurfaced in the 1970s, primarily in relation to decolonization conflicts and the Israeli-Palestinian conflict.

"At this stage, there were three opposing camps. The Western Bloc wanted to swiftly take action against terrorism, without bothering to first establish a definition. The Non-Aligned Movement, which included the Arab states, wanted to distinguish terrorism from national liberation movements. And the Eastern Bloc took a more ambiguous stance," said Sire.

Recognizing the difficulty in getting consensus on a general definition, the UN adopted a more pragmatic approach and set out to criminalize various violent acts considered to be forms of terrorism through specific conventions.

A concept that reflects the balance of power

The 1990s marked a major turning point. "The UN Security Council took charge of the organization's counter-terrorism efforts and adopted a new strategy: rather than defining terrorism, it drafted a list of actors considered to be terrorist groups," said the PhD student. This more technical and diplomatic approach meant that action could be taken even though consensus on the definition still hadn't been reached. But the lack of a definition also meant that transparency and human rights became secondary considerations in the fight against terrorism.

After the September 11 attacks in 2001, counter-terrorism became a priority for all states, which suddenly had to develop their own instruments on the matter. Cooperation between national security agencies increased, most notably through Interpol.

"The problem was that, under the pretext of counter-terrorism, the countries with the greatest influence were able to impose their views of what does and doesn't constitute terrorism," noted Corentin Sire. “The US-led War on Terror is a good example of how a global superpower can sometimes contravene international law in the name of fighting terrorism."

In Sire's view, the situation has created a fundamental paradox. The UN, which was founded on the principles of equality between states and the primacy of international law, "now finds itself grappling with a concept that both reflects and reinforces the hierarchies of the international order."

Can a more balanced approach be found?

Given the potential for abuse, there have been efforts to restore the role of international law and the UN General Assembly. In 2006, the United Nations Global Counter-Terrorism Strategy was adopted to establish a common international approach to combating terrorism. Since then, the instrument has been reviewed every two years. In 2017, the Office of Counter-Terrorism was created within the United Nations Secretariat.

"While these developments have added complexity to the UN's approach to fighting terrorism, they also provide a framework for it," said Sire. "Even though establishing a universal definition is still perceived as impossible, the UN is at least trying to ensure that counter-terrorism activities do not lead to violations of the fundamental principles of international law. In practice, however, the UN has a hard time imposing limits on counter-terrorism measures, as doing so could infringe on state sovereignty."

Sire warns that we should be wary whenever an actor invokes terrorism to justify a specific act. "Anything—including the most reprehensible actions—can be justified in the name of combating terrorism."