Most european railroads are electric, and I believe there maybe two reasons for that. One that they have fewer miles of track, fewer spers, and sideings, so the cost is much lower.
The other may be that because of the lower density of automoble trafic, they have a larger ridership of passangers. Where as in the US only a few passangers lines are self paying.
Most of the rail lines in the us carry freight, so much so that over 50% of the freight is carried by rail. In europe the freight number is around 10%.
In europe much more cargo travels by the slower river barge (I assume slower is lower cost, or why use it). In the US the rail trafic moves slower, mainly because of the trafic density (There are some equipment, and people shortages also).
In essesence our railroad operates like europes river barge.
However I have been seeing trains here pulled by two or more 4000 HP engines, so at about 1kw/HP, that would translate to 8MW moving load. If we assume a cantaneory voltage of 800 V, the cantaneory would need to be able to deliver a 10,000 amp or more to a train. Again we have a standard or cost issue.