What is the "race problem"? The disproportionate outcomes in the United States of people from different racial groups. Higher incarceration rates, higher rates of poverty, lower rates of educational attainment. Etc.
More breakdown on incarceration rates
Spoiler
Poverty Rates
Higher Unemployment rate for the same Educational attainment.
So what is the cause of this?
Racism?
Culture?
Motivation?
Societal Structure?
Genetics?
Something else?
(this would be a bit better as a poll )
For those interested in exploring the question I highly recommend the book: Divided by Faith: Evangelical Religion and the Problem of Race in America.
The cause is a combination of all, but I think that culture is the most important cause.