My car weighs in at about 4500 pounds. At 65 to 70 mph it takes 350 to 450 feet to stop the car.
A semi (loaded) can weigh in at 80,000 pounds (or more). At 65 to 70 it takes more than 1000 feet to stop the semi.
On weight alone in an accident the truck outweighs my car 20 to 1. Bad odds all around.
That's why you shouldn't pull into the "safety zone" a trucker leaves between themselves and the traffic ahead of them.
Give 'em room, give 'em respect and keep your lights on low beam.