Long-haul trucking or freight transportation is the lifeblood of America. In Russia, it's all about the rail system, but in the U.S., it's all about the highway system.Over the years with all the ups and downs of the freight transportation market, I often wondered what is it that drives the cost of freight transportation? When diesel prices decline, brokers are quick to point this out as the driver of the much lower linehaul price. Diesel prices go down, this affects diesel surcharge rates, and so clients pay brokers less money with which brokers need to make a profit.I guess that makes sense. But I wasn't satisfied and so I dug a bit deeper. What are these elusive freight transportation cost drivers?