There's a parade being held for the 4th of July. You want to see it, but don't want to fight all that traffic, so you hop on a train heading to where the parade is taking place. The train-car is crowded. Wall to wall people. There are 200 Americans on this train*.
You begin to wonder "Who are these people that share this train with me?"
Let me tell you who they are, because many people think "this is my train" or even worse "this used to be my train, but this is their train now".