I think long haul trucking is a perfect fit for a driverless vehicle ..
It is, and Daimler (Freightliner) and Volvo have been testing semi-autonomous trucks for a few years now.
They have also been testing multiple self driving trucks in a convoy playing follow the leader or "platooning" as they call it where the lead truck sends commands to the vehicles behind it to accelerate, decelerate, brake etc.
I say semi-autonomous as the driver is still needed for the first and last mile of the journey.
Backing into loading docks, coupling and uncoupling trailers etc.
Once that is able to be done without the the driver's interaction, then and only then will they become true drones.
We are still a long way off from having totally driverless vehicles, private or commercial.
The challenge in the short term is people who are behind the wheel of semi-autonomous vehicles will become complacent when they are still supposed to be paying attention to the road possibly causing more crashes than the technology is supposed to eliminate.
There are already reports of vehicles using adaptive cruise control still running into vehicles that have stopped or slowed to quickly. Short term I think I will be even more scared behind the wheel when these other idiots think it's ok to be texting and playing with their phones or tablets when using a self driving vehicle when they should still be paying attention to the road.
This person thinks we still have a very long way to go if it will even happen at all:
Fully autonomous cars are unlikely, says America’s top transportation safety official