Toni Morrison is trying to tell us not to be cruel to anyone even though we are rich or poor educate or uneducated, masculine or feminine. We should not take advantage of others because we are all humans. This means that everyone should be treated equally. If we do not stop oppressing others then more of us will be oppressed by the ones who were oppressed so it will affect everyone.
Nowadays, domestic violence is one the main oppression face at home because when a husband abused of his wife, she might abused of her children by neglecting them care or nutrition as a way of comfort. When these children grow older they would apply what they experienced to their children because most cases reported on domestic violence had to deal with people who live their childhood in home with domestic violence occurring. So it is like a genetic disease that is transmitting over the generations.
Another oppression that still exists is gender oppression. Men earned more income than women earned even though they have the same skills, same level of education, and they are doing the same job. Not in salary there is inequality but also in politics because there is no woman president and there are more men than women working in the congress.
One of the biggest oppression that exists nowadays is the war in Iraq. Thousands of people died in the war. Americans are forced to participate in this oppression because of the draft. In fact a strong country like the United States which was oppressed by the British before the Independence Act is now oppressing a small country like Iraq.