"Driver of the vehicle was pushed underneath the tractor trailer in entrance"...why does the US not require tractor trailers to get bumper heights/reinforcement that might prevent this? I am guessing due to the fact trucking organizations lobby against it. In Germany, all trucks have this. Yeah I googled it http://pulling-double-trailers94948.blogrelation.com/10383796/getting-my-pulling-double-trailers-to-work