Why only 3 black grandmasters, none of which are American?

There's also the fact that the average IQ of black people on average is 80 or so. You can look this up on Wikipedia. Just to be clear, its not saying that its genetic in origin (in fact the idea that race even has a genetic component is considered false by many biological anthropologists). A lot of psychometricians believe it can be explained entirely due to environmental origins, such as the generational effects of slavery, pro-gang black culture (i.e. rappers who often include anti-police lyrics), or the abnormally high rate of single-parent households, specifically single mothers, in black society. So basically, due to poor education and negative cultural and family influences, they will tend to have fewer opportunities, as well as in general a lower than average intelligence quotient as measured on standardized tests, leading to a reduced interest in chess and other intellectual pursuits.

Also to Mark the Destroyer and his supporters, the suggestion that asking this question is racist is completely absurd and actively harmful to the black community. Students who are PhD candidates in political or social science study these issues all the time in different contexts. For example, different races experience markedly different living conditions in the USA, and have different criminal conviction rates, and its important to understand why these things are true so that the government can implement policies aimed at fixing the problem and making things better. Believe it or not, there are other reasons (if you spend 5 seconds thinking about it) besides RACISM!!!1111 for asking these questions.

If you suppress all conversation and call everyone inquiring into these problems as racist, then those problems will never be solved, and institutional issues will never come to light (if they do indeed exist). Part of what the OP is doing is raising awareness on this issue so that it may be solved. Its attitudes like yours that only make things more problematic.