Celebrating Columbus Day?

Christopher Columbus is credited with discovering the Americas on October 12, 1492.  Many countries in the Americas, including the United States, celebrate this momentous event with a national holiday, parades, speeches and other commemorations.  However, there is a growing and rather vocal group of people (particularly the ancestors of the indigenous populations) who believe that to celebrate such a man is wrong.  Look up some of the opposition groups' positions and then, based on what you have learned about Columbus, make a reasoned argument as to whether or not any country should celebrate Columbus Day.