Hmmm. Interesting article, but to me it has nothing to do with "why US railroads declined". That actually goes back to the Autobahn. When Hitler took power in 1934, the Nazis were quick to realize the military advantage of a superhighway system over railroads - you couldn't move heavy loads as fast, but you could move troops quicker and it was a lot harder to cut the line by bombing it since trucks can steer around damage, trains can't steer at all.
General Eisenhower was very impressed with the autobahn - in the US anyone traveling any distance went by train, any long distance cargo went by train, since roads and highways were small, primitive, unpaved in some places, and difficult to navigate since there was no consistent connection. Most troop movements in the continental US in WWII were by train, fortunately the enemy didn't have the long range bombers needed to tear up our railroads, but if they had, then some type of highway system would have been critical. So Eisenhower becomes US President in 1953, and decrees the US shall have an Interstate Highway System. Fallout from that, it became faster, cheaper, and more efficient to move small cargoes and people on the highways over short to medium distances, and the introduction of the Boeing 707 in 1958 meant trains could no longer compete for long distance passengers and mail either. That's what caused the decline, the railroads killed the boat canals because they were more efficient at the time, the superhighways killed the railroads because they were more efficient and/or convenient at the time. Gas ain't as cheap or easy to come by as it was in the 50's, so it's possible the railroads will make a big comeback, steel wheels on steel rails are still the most energy efficient way of moving stuff around.
