Why Didn't I know?

After being enlightened by Shorto's "The Island at the Center of the World", I couldn't help but thinking why I didn't know much of this story. As a history buff in high school and now a history major at Hamilton, I would like to think that I am at least fairly well versed in American history especially that of New York state. However, I think many history courses have downplayed the importance of New Amsterdam/New York City to the survival of the union. I knew so little about its importance to the colonization, defense, and industrialization of the continent.

So my question is why didn't I know? I suppose it could be that it was taught and I overlooked it. But I hope that's not the case. Instead, I wonder if the colonies' non-English roots could be the reason. As I look back, the emphasis was always put on the colonies in Virginia and Massachusetts. The stories of these other colonies are just as interesting but they were downplayed while their importance is astounding. Any other ideas?