On Dec. 19, the Senate unanimously passed legislation that made lynching a federal crime. Proposed by Sens. Cory Booker, Kamala D. Harris and Tim Scott, the Justice for Lynching Act classifies lynching, “the ultimate expression of racism in the United States,” as a hate crime. In its findings, the bill states that at least 4,742 people, mostly African Americans, were lynched in the United States between 1882 and 1968, and that Congress had considered nearly 200 anti-lynching bills in the first half of the 20th century without passing any of them.

For more than a century, Southern resistance and Northern indifference has undermined such legislative efforts. Why? Because lynching had remained a powerful terrorist tool to maintain white supremacy.

The passage of the Justice for Lynching Act is a reminder that change in America is painfully slow. This legislation took more than 100 years to pass, despite a long-standing recognition of lynching’s immorality, ultimately reminding us of the pervasive way in which racial violence has been ingrained in all aspects of law, politics and culture.

The campaign against lynching began in earnest in 1892 when Ida B. Wells, a journalist and social critic who had been born a slave in 1862, published “Southern Horrors: The Lynch Law in All Its Phases.” She lectured publicly and exposed the rape myth — falsely accusing the black men who were murdered of raping white women — that was used to justify lynching as a rationale for racial subordination. As a journalist, Wells-Barnett (she married in 1895) challenged professed ignorance about lynching with facts, a strategy adopted by the civil rights organizations that would follow her lead.

Building on these efforts, the newly founded National Association for the Advancement of Colored People (NAACP) published a report, “Thirty Years of Lynching in the United States, 1889-1919,” denouncing the United States as “the only advanced nation whose government has tolerated lynching.” The report quoted President Woodrow Wilson, who in July 1918 condemned lynching. But Wilson’s condemnation meant little next to his earlier enthusiasm for “Birth of a Nation,” a film that further legitimized vigilantism. Despite Wilson’s appeal, the report notes, “lynchings continued . . . with unabated fury.” ...