Similarly, the unique role the railroad played does not negate the atrocities that were part and parcel of its development. When talking about civilization-progressing technologies, it is not possible to focus entirely on the technology.

Unless we're also willing to talk about Facebook as a generation-redefining technology that altered how people interact, without mentioning the negatives. I'm sure people will attempt to do that a century from now; it will be wrong then as well.