Paris Will Host the 2024 Olympics. Now, France Has to Ensure They’re Safe

The timing in Paris early Friday morning could hardly have been more ominous. As the Mayor of Paris and top French officials were on a flight from Lima, Peru, where the International Olympic Committee had awarded them the right to host the Summer Games in 2024, events were unfolding on the ground.

As the airplane approached Paris, a man wielding a knife lunged at a soldier in the heart of the city, in the heavily used Chatelet Metro station, while expressing support for ISIS, according to police. The timing was almost certainly unintended, and the attacker arrested before he inflicted any injuries. And yet, the assault served as a telling reminder—if any was needed—of a crucial question that will loom over the city ahead of August 2024: Just how safe will the Paris Olympics be?

Of course, these Games are still seven years away. But officials say they are already intently working on how to properly secure Paris for the hundreds of thousands, perhaps millions, of people they expect to pour into the city for the Olympics.

The effort is particularly focused on the 35 sporting arenas where the Olympics will take place—including beach volleyball at the foot of the Eiffel Tower, swimming and rowing on the Seine River, and horse-jumping at the Chateau of Versailles. Another major site will be the Olympic Village, planned for about 14,500 athletes, that will be built in the low-income, northeast district of Seine-Saint-Denis.

“We know that the Games constitute a target,” Etienne Thobois, Director General of the Paris 2024 committee, told the French paper Libération on Thursday, hours after the International Olympic Committee awarded Paris the 2024 games in Lima. “We rely on very precise knowledge of our sites, the advice of police, and the experience of Euro 2016,” he said.

This was a reference to the European soccer championships which took place in Paris and across France last year, little more than six months after ISIS-trained gunmen-suicide bombers rampaged through the capital, killing 130 people at sidewalk cafés and a music hall, on a balmy Friday evening.

Yet the Championships passed without major incident; the large contingent of soldiers and police faced more problems from brawling fans than from terrorists. For the Olympics, Paris will install extensive videosurveillance systems around sporting venues and the athletes’ housing, Thobois says.

All of that will cost money, though — and how much has become a matter of hot debate. Out of a budget of $7.3 billion to host the Games—a fraction of the $51 billion Beijing spent on the 2008 Games, and just over half the amount spent to hold last year’s Rio Olympics—the Paris organizing committee has so far budgeted only €186 million ($221 million) for security.

Experts believe that total is far too low. They point to London, which budgeted almost exactly the same amount for security during the Olympic Summer Games in 2012. That was before a series of deadly attacks on the London transport network hit the U.K. capital, one day after they won that hosting bid in 2005. By the time the London Olympics opened in summer 2012, security costs had ballooned to about $1 billion.

“Paris could find itself in a similar situation,” says Alexandre Delaigue, an economist who has heavily criticized the low-ball budgeting of the Paris Olympics organizers. “It is impossible to predict the security context of 2024,” he told Libération on Thursday.

Parisians have good reason to be wary. In the nearly two years since the Paris attacks of November 2015, France has been under a national state of emergency, with the military and police having broad powers to search and arrest suspects, and hold them for extended periods. The signs of alert security are everywhere in Paris: Armed soldiers and gendarmes now patrol major avenues and train stations, and security guards search shoppers’ bags at stores.

The specter of another major attack courses through Paris like a low background hum. Many here believe it’s inevitable, but few discuss the possibility openly. Numerous attacks or attempted attacks have occurred this year alone, including at major tourist hubs like Notre-Dame Cathedral, the Louvre Museum, Orly Airport, and Champs-Elysée Avenue. Many mirror Friday’s attack, in which lone assailants target armed personnel with knives or firearms.

And the threat could be with France for years to come. Europe’s security forces fear that terrorist incidents could rise, and turn far more professional, as large numbers of ISIS’s foreign fighters from Europe begin drifting back home from battlefields in Syria and Iraq. The jihadist group’s “physical caliphate” has almost entirely been defeated by the U.S.-led coalition. Now the surviving fighters—well trained and battle-ready—are coming home, some slipping in unnoticed on their E.U. passports, in order to avoid arrest.

‘This return migration has already started,” Otso Iho, senior analyst of Jane’s Terrorism and Insurgency Center in London told TIME on Thursday. In the years ahead, “they are likely to inject added capabilty to existing Islamic networks, combat experience, small-arms handling, ideological rigor, ability to construct explosives, etc.,” Iho says.

This presents a particular issue for France. About 1,800 French joined jihadist groups in Iraq and Syria over the past five years, the greatest number of any European contingent, according to the Soufan Group, a terrorism research organization. Whether these returnees will still pose a threat in 2024 is impossible to predict. Parisians now have seven years to watch, wait and plan ahead.