Nobody is gonna blame you specifically for slavery. That's nonsensical. I'm sure you're a good person yourself. But what I need you to understand is how the racial dichotomy in America was created. No one is accusing you of anything, but as a white individual, you should be aware of certain privileges that you have as a result of being what society considers "the norm", and you should also be aware that if people of color have hostility toward you, it's not necessarily because of you as an individual, but because of what that people associates being white with.

People of color all have things they have to deal with that white people do not. It's the chain that we wear that you are free from. Again, nobody is blaming you for slavery, but they do want you to understand the plight that they face, to be aware that your experience in life is not universal, that your white skin has imbued you with certain privileges that non-whites do not have. Only in understanding and accepting the different struggles that we face can we hope to have a society free of racism.