Actually, the reason Blacks dislike the Republican party is not because of the past, but the code words the Republican party still uses in their propaganda.
That is not going to change. Why? Well, conservatives detest change of any kind. Especially one that include themselves.
Why do these 'words' matter so much when they come from the republicans? When the democrats use similar or worse 'words', you can see the hands covering the ears (there is no acknowledgement for dems uttering racist remarks, only choosing inappropriate terms). Do code words include: low taxes, smaller gov, protected borders, equal protection under the law, laws applied equally, national security? (I am not saying that is what repubs ACTUALLY do, but that is the platform they use.
Can you be more specific? If blacks are sensitive to an issue, is it okay to ask using proper words, or do blacks prefer a 'word dance' where nobody understands what the conversation is. I have noticed when using 'sensitive words', if the conversationalists are calm, both sides learn something (mostly, that they are not that far apart).
IMHO, most racist charges are out of ignorance, not racism. If no one tells you how they feel, it is really hard to guess what is going on inside the head.
So, please, be specific, misunderstanding is perpetuated by vague statements.