President Barack Obama has pledged $8 billion in tax dollars to build a national network of high-speed rail—trains that can carry passengers at speeds in excess of 150 MPH. But the Supertrain fantasy was a mistake back in the 1970s, when it gave rise to one of the most expensive—and rotten—TV shows in history. And it's just as much of a wreck in the 21st century for at least three&...