Columbus is an paradox. Great sailor, horrible administrator. The most celebrated and most hatted explorer of the New World. He was not the first European to come to the Americas. Finally, Columbus claimed a small Earth existed and thought he discovered Asian islands for the longest time. The continents are not even named after him.
However, Columbus' journey showed to the Europe that there was a New World. That the Europeans with their technology and Crusader-mindset could conquer it if they applied themselves. Saints and damned sinners came to the Americas and left their mark on the land and on the people, including the European colonists, American Indians, and Africans.
No one can deny Columbus changed the world. In evaluating whether or not this was a "good thing" one must remember history is still on going. All Americans, Northern and Southern, are children of Columbus and the rest of the world effects us and is affected by us. Continental Americans must play a direct and indirect role in bettering the world if Columbus' legacy is to be good.