A court sketch shows Abdelkader Merah, left, and Fettah Malki, right, in a Paris courtroom during their trial for complicity in a series of shootings commited by Merah’s brother in 2012. (Benoit Peyrucq/AFP/Getty Images)

This was the case that started it all: the first chapter in France's struggle with homegrown Islamist violence.

In 2012, between March 11 and March 19, Mohammed Merah, a 23-year-old French citizen of Algerian origins, murdered seven people: first three French police officers, and then a rabbi and three children at a Jewish school in the southwestern city of Toulouse.

The Merah affair was a shock at the time — pointing to an attacker raised in France rather than a militant who slipped into the country to carry out previous Islamist-linked strikes for groups such as Lebanon's Hezbollah or factions that grew out of Algeria's civil war in the 1990s.

In the years since Merah's bloodshed, the episode has come to reflect the elements in many other recent attacks: youth against authority, Islamist extremist against Jew, and, perhaps most of all, French against French.

This week, the Merah case was brought to trial in Paris, although Merah was killed at the end of his rampage.

On the stand now are two of his alleged accomplices: Fettah Malki, 34, accused of providing Merah with a weapon, and Merah's older brother, Abdelkader Merah, 35, suspected of helping his sibling steal the scooter later used in the attacks. The elder Merah was born in France, and Malki came to France from Algeria when he was 11.

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But for many, the trial is about more than seeking convictions. Its real purpose is seeking answers about the origins of a relentless wave of terrorism in France — ranging from major carnage in Paris and Nice to smaller strikes such as a knife slashing that killed two people in Marseille last Sunday.

"This trial is historic," said Patrick Klugman, a lawyer representing Samuel Sandler, the father and grandfather of Merah's Jewish victims, in opening remarks Monday.

"Merah is dead, but it is essential to understand what happened for the memory of the victims and their families," he added.

Jonathan Sandler, a rabbi, was 30 when he was killed. His sons, Gabriel and Arieh Sandler, were 5 and 3, respectively.

If convicted, Malki faces up to 20 years in prison, and Abdelkader Merah up to a life sentence. Verdicts are expected Nov. 3.

In recent years, no other country in Western Europe has been hit by the same frequency of terrorist violence. Gilles Kepel, an acclaimed French political scientist, recently observed in a best-selling book that Islamist-inspired violence "is not exclusively French," but "the French case is stronger and deeper" than those of other neighboring countries.

Since the beginning of 2015 alone, nearly 240 people have been killed in attacks linked to Islamist groups such as the Islamic State. Significantly, the majority of perpetrators have been longtime legal residents in France or French citizens. Others have had passports from other European Union countries.

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Youth radicalization has been a particularly perplexing problem for authorities in France, which has Western Europe's largest Muslim population.

More French citizens have decamped to fight for the Islamic State in Iraq, Syria or other locations across the Middle East, according to terrorism experts. Of the roughly 6,000 fighters who left Europe to join the Islamic State, approximately 1,800 were French.

Merah's attack — believed to be linked to al-Qaeda — predated the emergence of the Islamic State.

"But his actions have inspired a lot of radicalized individuals . . . He was someone who by his actions encouraged so many others to follow," said Jean-Charles Brisard, director of the Paris-based Center for the Analysis of Terrorism, a security think tank.

Notably, police records show that Merah was mentioned in social media posts by many in the immediate circle of Abdelhamid Abaaoud, the Belgian-Moroccan mastermind of the November 2015 Paris attacks, which claimed 130 lives.

For others — especially France's Jewish community, the largest in Europe — the Merah case foreshadowed the anti-Semitism often on display in a number of other terrorist attacks that followed.

In January 2015, following the attack on the offices of the satirical newspaper Charlie Hebdo, a related terrorist affiliated with the Islamic State targeted a kosher supermarket on the outskirts of Paris, killing four people.

In April 2017, Sarah Halimi, an orthodox Jewish schoolteacher, was murdered in her Paris apartment and thrown from the window. Those attacks and others spurred a spike in immigration to Israel by French Jews, although departures have recently dropped.

"This trial is also about anti-Semitism that kills and wants to put our modern societies in danger," said Francis Kalifat, the director of the Representative Council of French-Jewish Institutions, France's largest Jewish advocacy organization, in a statement.

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