I'd argue the main difference is that the infrastructure in the US is private, while it's publicly owned in Europe. This allows some amount of subsidy towards the infrastructure, like is done for highways, allowing passenger trains to exist.
Since then railroads have to be completely self-supporting in the US, they focus on how they can achieve the highest productivity: giant, slow trains on shoddy track.
It also means the infrastructures are competing with one another, so there are redundant, shoddy, competing rail networks, rather than a network for slow and heavy freight trains, and a network for fast and light passenger trains.
Since then railroads have to be completely self-supporting in the US, they focus on how they can achieve the highest productivity: giant, slow trains on shoddy track.
It also means the infrastructures are competing with one another, so there are redundant, shoddy, competing rail networks, rather than a network for slow and heavy freight trains, and a network for fast and light passenger trains.