Actually trains are quite important to maintaining the global economy. Freight trains can ship hundreds of times more cargo than a single semi could. Passenger trains like Amtrak or ViaRail give small isolated communities access to the rest of the world as well as give commuters another option besides driving or getting groped by the TSA for a flight. All in all, a good rail network is a major advantage; it’s why the US was such a major power in the late 19th-early 20th century and is why China insists on pushing its New Silk Road railway lines today.
