Submarine landslides pose a direct threat to offshore infrastructure, and an indirect threat to coastal communities via tsunami generation. Recent studies have investigated the potential role that submarine landslides play in causing tsunamis on the U.S. East Coast. This paper quantitatively assesses submarine landslide hazard offshore Long Island and New Jersey, as an example, but the method herein can be applied to the entire Atlantic margin. Using publicly available bathymetry, surficial sediment data, undrained shear strength values, and earthquake ground motion predictions, we map the conditional probability of slope failure over our entire study area. We calculate this probability using a first-order, second moment estimate of the variance of critical acceleration needed to overcome the resisting forces in the infinite slope stability analysis. We show that this first-order, second moment approximation serves as a convenient and computationally efficient way of assessing submarine landslide hazard over a broad region, while also accounting for the significant uncertainties in the slope stability parameters.