“The first requirement of a slave society is secure borders. We do not like to think of the United States as a police state, a nation like East Germany that people had to escape from, but the slaveholding states were just that. Indeed, after the Fugitive Slave Act of 1850, which made it easy for whites to kidnap and sell free blacks into slavery, thousands of free African Americans realized they could not be safe even in Northern states and fled to Canada, Mexico, and Haiti.”
