What is the 15th Amendment?
Rights not to be denied because of race
This means that no matter what your race is your human rights cannot be neglected or disregarded. You are human and no matter what we see on the outside our insides are all the same. We are living, we are breathing... We are all human beings. Just because of ones thoughts on our appearances doesn't mean we are what his/her judgements say. It's what we do and who we are, not what we are "thought" to do or what we look like.
This is important to the american people because at first there was segregation against the Natives and slavery towards the Africans. As a country we knew this was wrong and needed to find a way to end this. We knew that despite the color, they were just like us and they don't deserve the labels or the torture we've put them through.