So-called “truck attacks” have grown in frequency around the world in recent months, as the vehicles, chosen for both their size and offering of anonymity, are used by terrorists to drive at high speeds into crowded pedestrian areas. But economic indications are that these vehicles will be among the first to become fully autonomous, which could play a role in mitigating their use as rolling weapons.

The latest instance of such an attack came on Wednesday, when a man drove a truck into a crowd and stabbed a police officer, resulting in the deaths of at least three people.

Vehicle ramming attacks have a long history and seem to be becoming a preferred method for terrorists. In the past year alone, there have been five such attacks. They occurred in Nice, France, at Ohio State University, in Berlin near Christmas, in Jerusalem, and now in London.

According to the FBI, vehicles are being selected as weapons because “vehicle ramming offers terrorists with limited access to explosives or weapons an opportunity to conduct a homeland attack with minimal prior training or experience.” In addition, a commercial truck provides a high degree of anonymity. Given their ubiquity on the roads, they are not viewed as potential weapons, thus slowing the response time of victims and law enforcement alike. During the Nice attack, for example, The Washington Post reported that “footage shot from cellphone cameras shows some people standing idly while others run as the truck accelerates into the crowd, reinforcing the notion that many had no clue they were being targeted.”

But the impending widespread introduction of autonomous vehicles could substantially decrease the viability of this tactic in the future, as it becomes harder, even impossible, to get a vehicle to ram pedestrians.

Recent projections place commercial truck drivers on the short list of jobs tipped for automation, indicating that this change is coming sooner than many might think. Several newer companies, including Elon Musk’s Tesla and the Uber-owned startup Otto, are actually developing these vehicles today. More well-established vehicle manufacturers like Mercedes and Volvo are also reportedly seeking to enter the market.

Otto is just the beginning.

Even low-end estimates suggest that as many as 1.7 million truckers could be replaced by autonomous counterparts within the next ten years. That number could rise to be as high as 3 million. That’s 3 million trucks without manual drivers. The roll-out of autonomous private cars will not be far behind.

By the time policy regulations — even in fast-acting progressive municipalities — are put into place that might outlaw work trucks from trundling through city streets, it’s entirely possible the industry may have eliminated them by then.

Those self-driven vehicles will have the ability to make complex decisions regarding how best to protect pedestrians. Using a truck as a weapon will no longer be as easy as hitting the gas and turning the wheel.

Autonomous Truck Hacking

The possibility of hacking these vehicles still remains, of course. But that sets the difficulty bar higher than it is currently, undercutting the primary reason an attacker would even gravitate toward the vehicle ramming method.

To wit, there is already proof that trucks that can think for themselves have real potential to save lives. During the Christmas market attack in Berlin, the assailant’s truck reportedly stopped early on during the attack. It was originally believed to be because the driver was wounded, and unable to continue. Authorities later altered that explanation.

Pursuant to 2012 EU regulations, the truck had been outfitted with an automatic braking system, designed to stop the truck on its own if a collision was detected. That, authorities said, is exactly what happened, saving many lives. When the trucks just drive themselves, that could save many more.

Photos via Getty Images / Jack Taylor