The economic costs of war and threat of war

Before World War I Russia, as a security measure, developed her rail system with a different width of track than usual. (I'm re-reading Barbara Tuchman's The Guns of August.)

This was done so that when Germany eventually invaded Russia the German rail cars would not be able to use the Russian tracks.

Of course, it also meant that everything about the Russian railroad was non-standard and more expensive and that it was hard to import or export goods since everything had to be carried from one train to another train at the border.

And the inadequacy of the Russian rail system made her seeming advantage of a huge population under arms all but useless at many junctures in WWI.

Think of it... a railroad system incompatible with everyone else's rails.... in a nation with some of the greatest distances needing to be covered of an nation on Earth.

An incredible economic cost, and all necessitated by the constant threat of war and invasion.