The vast majority of the time, train tracks are, for all intents and purposes, speed bumps. They make the ride less comfortable for a moment and they slow drivers down for a moment. It's important, however, to remember that every now and then a vehicle that weighs hundreds of tons comes hurtling down the "speed bump" at high speeds. It doesn't matter what your're driving, it will win.
Case in point: this Seattle area truck full of Mountain Dew turned right in front of a train, and now somebody in the Northwest must go through withdraws from their usual dose of vaguely citrus flavored beverage.