Another civil use of field railroads was in the construction of the Panama Canal. Nearly all of the dirt and rock was hauled by rail, and the tracks shifted constantly to keep up with the steam shovels. This project was begun by the French, using narrow gauge equipment, but completed by Americans, who switched to larger, standard gauge wagons.
That's significant, but was it decisive? (I'm really asking, am not sure myself.) I note moving of division sized units by railway also happened during the crushing of the 1948/9 revolutions. *Lunatic*, n. One whose delusions are out of fashion.
Railroads are certainly on this list.
Nor was the importance of railroads neglected at the time. Opponent's railways, when they could not be taken over, were routinely ripped up. The Fates are kind.
After doing some read-up, I submit that railways were decisive in the American Civil War, particularly the 1864 campaigns. *Lunatic*, n. One whose delusions are out of fashion.
Benzol engine locomotive crosses a half-finished bridge with train to less-finished parts of the Alzingen-Oetrange line in 1915.
A large assemblage of field railway steam locomotives at a tunnel widening project in 1929. *Lunatic*, n. One whose delusions are out of fashion.
