Paris is a city swamped in security. Forty thousand barriers divide the French capital. Packs of police officers wearing stab vests patrol pretty, cobbled streets. The river Seine is out of bounds to anyone who has not already been vetted and issued a personal QR code. Khaki-clad soldiers, present since the 2015 terrorist attacks, linger near a canal-side boulangerie, wearing berets and clutching large guns to their chests.

French interior minister Gérald Darmanin has justified these measures as vigilance—not overkill. France is facing the “biggest security challenge any country has ever had to organize in a time of peace,” he told reporters.

Parisians are grumbling about road closures and bike lanes that abruptly end without warning, while human rights groups are denouncing “unacceptable risks to fundamental rights.” For the Games, this is nothing new. Complaints about dystopian security are almost an Olympics tradition. Previous iterations have been characterized as Lockdown London, Fortress Tokyo, and the “arms race” in Rio. This time, it is the least-visible security measures that have emerged as some of the most controversial. Security measures in Paris have been turbocharged by a new type of AI, as the city enables controversial algorithms to crawl CCTV footage of transport stations looking for threats.