The black-white differences in marriages in the US are striking. While 83% of white women between ages 25 and 54 were ever married in 2006, only 56% of black women were: a gap of 27 percentage points. Wilson (1987) suggests that the lack of marriageable black men due to incarceration and unemployment is responsible for low marriage rates among the black population. In this paper, we take a dynamic look at the Wilson Hypothesis. We argue that the current incarceration policies and labor market prospects make black men riskier spouses than white men. They are not only more likely to be, but also to become, unemployed or incarcerated than their white counterparts. We develop an equilibrium search model of marriage, divorce and labor supply that takes into account the transitions between employment, unemployment and prison for individuals by race, education, and gender. We estimate model parameters to be consistent with key statistics of the US economy. We then investigate how much of the racial divide in marriage is due to differences in the riskiness of potential spouses. We find that differences in incarceration and employment dynamics between black and white men can account for half of the existing black-white marriage gap in the data.