I've noticed that almost every time someone does anything that could be reasonably construed...
... as racist, there is always a reasonable answer to why it shouldn't matter.
I was young.
It was just a joke.
I have black friends.
You don't know what was in their heart and minds.
There is a distinction between being a racist and normalizing racist behavior. You can normalize racism without being a racist or desiring racist outcomes. Most of those in the majority don't understand what those being targeted by such behavior feel and or live through on a daily basis.
Many white Americans voted for Trump because they are afraid of not being in the majority. They may not be racist but they normalize racism by their votes. Change is scary to some, and it's hard to change thoughts and opinions you've held since you were a little child. That is why we still have redskins used in sports teams at the high school and professional level.
As Democrats we need to stand up for our beliefs. We need to be open to change, and we need to view this through the eyes of those who have been living this since the founding of our country. Fear of repercussions shouldn't matter more than doing the right thing.