Actually, far more whites than blacks are on welfare - but that's because there are far more whites in the population. You're right, though, that as a percentage a much larger % of blacks than whites are on welfare, and a much larger % of blacks have been on welfare for a longer time period, generation to generation, to where it has become a lifestyle choice rather than a safety net.
And yes, liberal policies of enslaving blacks to dependency on government is the cause, because it ensures their ovewhelmingly Democrat voting pattern. Break free, folks; it's the Democrats that have put y'all back in chains. (Credit to Joe Biden)