Thats the estimate of current US steel and US made portland cement costs. Too little of it in America.
US made steel has atrophied because of politics, blame the Clintons.Chinese steel IS cheaper, in more than one way, not suitable.Bigger profit margins.
Sooo.....
Whats really needed is new steel and portland cement plants IN AMERICA.
China pretty much put out of business portland cement plants, i know because i manage a concrete batch plant, years ago we had cement shortages in Alaska becsuse China used most of all cement production for the Three Gorges Dam.
Maybe it’s because in addition to concete and steel it will include guard posts, high tech cameras / surveillance systems, power/ data / utility lines, and access roads along the entire length. It’s not as simple as installing a chain link fence or security fence around your property.
JMHO