I was sure a black president would be able to address racial issues in the US and finally solve them.
That's an incredibly racist thing to say.
Just because someone is black does not mean they are competent to fix a problem.
Just because someone is black does not mean the problem in question can be fixed by a President.
Just because someone is black does not mean the problem can be fixed within a certain amount of time (i.e. the life of an Administration).
Just because someone is black does not mean they are more capable than a non-black person to fix the problem.
Just because someone is black does not mean they are not part of the problem.
Just because someone is black does not mean they want to fix the problem.
Just because someone is black does not mean they even understand the problem.