Scholars warn that another American civil war is increasingly plausible, if still unlikely; professional political commentators express greater concerns. This study examines the likelihood of another U.S. civil war by comparing perspectives of the 1850s with those of today by using a negative social capital framework as the analytic lens. The analysis finds striking similarities between the two periods. Yet, civil war is a relatively rare phenomenon in developed countries, and the analysis also points to contemporary mitigating examples. At least for the foreseeable future, more likely are trajectories moving toward other types of social unrest short of civil war: ongoing civil strife, additional insurrections, decades-long intraregional political gridlock causing widespread administrative dysfunction, and even a failure to relinquish power. The negative social psychology has already had an extraordinary impact on public administration and is unlikely to decrease in the near term; it may yet increase exponentially as it did in the 1860s.