Why do some people protest against Christopher Columbus being seen as a hero? please answer

He used slavery and violence to a lot of Native Americans

Explanation:

As a lot of people know, slavery was common in Native American days, and Columbus was no stranger to that. This is the reason why Columbus is sometimes hated.

i confess that there are several parts of this constitution which i do not at present approve, but i am not sure i shall never approve them: for having lived long, i have experienced many instances of being obliged by better information or fuller consideration, to change opinions even on important subjects, which i once thought right, but found to be otherwise. it is therefore that the older i grow, the more apt i am to doubt my own judgment, and to pay more respect to the judgment of others.

i believe it to be a democracy