Many forces are working to drive the decline in labor power. (Bloomberg)
Calvin Schermerhorn is professor of history in Arizona State University's School of Historical, Philosophical and Religious Studies and author of "The Business of Slavery and the Rise of American Capitalism, 1815-1860."

One hundred thirty years ago, white vigilantes shot some 60 African American farmworkers dead in Thibodaux, La.

In targeting black sugar workers, the gunmen were also targeting their union. It was a pivotal time for labor in the United States. Workers did not have a right to unionize, and strikers often risked not just their jobs but their lives. Hostile employers, though, were not the only obstacle. As the events of Nov. 23, 1887, showed, racism undermined class solidarity and the potential of the American labor movement.

The explosive issues in Thibodaux are still stirring politics today. Union strength depends on worker unity, but workers are divided by race. In 2016, white union households supported Donald Trump at rates not seen for a Republican since Ronald Reagan’s reelection in 1984. Trump exploited labor weakness by promising to be on the side of white workers, while Democrats captured nearly all the black union vote last year. Race, not economics, fueled these partisan rifts. Such racial divides today are helping to resurrect ideas from the Jim Crow South that have long undermined worker unity and infringed upon the ability of organized labor to stem falling worker wages and benefits.

The conflict between white supremacy and labor solidarity began even before the Civil War ended. After Louisiana ended slavery in 1864, the labor market favored comparatively high wages for black workers. Reconstruction policies helped, especially when African Americans voted and held office.

But by the 1870s, the rise of tenant farms and the decline of African American representation in politics thanks to Jim Crow laws forced sugar workers’ lives to slip back toward slavery-like conditions. With no money and no land to rent, sugar workers toiled in gangs, just like their enslaved ancestors. They lived in old slave cabins with meals provided by planters. Some earned the equivalent of less than $1 an hour today. Instead of cash wages, they were paid in scrip spendable only at plantation stores, which charged high prices.

Louisiana sugar workers went to the picket line to hoist themselves out of quasi-slavery.

After growers tried to lower wages even more, African American workers banded together in 1874. But what became known as the Southdown Strike was short-lived. It lacked the political support it needed to gain momentum, even with a Republican governor and African American sheriff in office. Growers benefited from militant white supremacists who nearly forced the governor out of office shortly after the strike.

As Reconstruction ended and the rise of Jim Crow increasingly narrowed or eliminated political opportunities for African Americans, Louisiana sugar workers sought outside help.

A 700,000-strong national labor organization boosted their strength. The Knights of Labor was a bread-and-butter union, focusing on wages, hours and dignity. It resisted radicalism and militancy. The Knights organized African Americans, farmworkers and women at a time when most unions organized white craftsmen only.

African Americans took part in the growing labor movement as a way to stanch political losses and build capital that supported upward mobility. In 1883, abolitionist and labor leader Frederick Douglass urged Americans to see unions as a struggle for a new emancipation, arguing that, “this slavery of wages must go down with the other.” Workers relied on unions, rather than parties, to press their interests.

Douglass’s contention was tested in 1887 when Louisiana sugar workers organized to demand $1.25 per day, which today works out to $2.71 per hour for a 12-hour shift. And they wanted cash not scrip.

But growers refused to bargain with them — not simply because the harvest had been poor, but because black workers had organized and threatened to overthrow the system of racial hierarchy. It was about the color line and not the bottom line. In response, planters fired workers and called on Gov. Samuel D. McEnery and white militiamen to evict the strikers.

Employers and governments utilized similar violent strategies across the United States to break strikes during the 1870s and 1880s. In Louisiana, a white sheriff’s posse murdered several black strikers during a confrontation in Patterson, and a militia unit mounted a bayonet charge on workers on a plantation in Lafourche. Terror sent some back to the fields.

But in Thibodaux, undaunted, black workers continued to organize to secure economic rights and to challenge the system of Jim Crow.

As the strike gained national attention, labor supporters saw it as a test of black organizing against Jim Crow. And indeed, the labor strike had become a powder keg for racial conflict.

District Judge Taylor Beattie declared martial law, letting a white “vigilance committee” seal off the town to African Americans. Vigilantes tried to provoke violence and, according to one newspaper report, “resolved that some pretext or other should be given so that a massacre might ensue.” Before dawn on Nov. 23, two white sentries were shot and wounded by unidentified snipers.

And then, it got even bloodier.

Jack Conrad, an African American worker, remembered what came next: “the regulators went about town shooting every colored person in sight.” He was shot in the arms and chest by his employer. Conrad’s 19-year-old son, Grant, was killed as he hid behind a barrel. One Knights leader was discovered in an attic, brought to the town common, told to run and then shot down by a firing squad.

Strikers “offered no resistance; they could not, as the killing was unexpected.” Bodies were dumped in an unmarked grave, and killings continued on surrounding plantations for days.

At the end of it, workers returned to the fields under the old terms. None of the gunmen were brought to justice. The federal government refused to investigate, while sugar planter Andrew Price, spotted in Thibodaux among the vigilantes, was elected to Congress the next year. Instead of running for cover, those involved stood proud of the atrocity.

The Thibodaux Massacre set back black farmworker organizing decades, and hostility to union organizing more broadly gained momentum in the South. While unions grew in the North with African American participation, Jim Crow was a union-buster. Massacres of African American labor organizers in Elaine, Ark., in 1919 and textile strikers in Marion, N.C., in 1929 were sequels.

Ultimately, Northern unions and their pursuit of economic rights proved to be a central force in civil rights struggles. Civil rights leaders connected racial equality and economic opportunity. Martin Luther King Jr. put it this way: “If a man doesn’t have a job or an income, he has neither life nor liberty nor the possibility for the pursuit of happiness. He merely exists.”

But as a result of civil rights victories in the 1960s, a Democratic Party coalition of Southern segregationists and Northern unionists cracked apart. Since the New Deal, Democrats had allied with Southern segregationists who tolerated unions so long as they were not in the South. Black civil rights were, in a profound sense, purchased at the expense of a strong and inclusive labor movement.

Democrats lost the white South as Republicans appealed to white workers as whites rather than as workers. In that political realignment, the Southern backlash was a frontal assault on unions.

And as industry shifted from the Northeast to the South, the legacy of brutal violence became a virtue that attracted businesses to move. New South boosters boasted of “cheap, nonunion labor,” in the words of historian James C. Cobb. Sun Belt capitalism promised pliable workers paid low wages.

Today, the Southeast has the lowest wages in the nation. Nationally, nonunionized workers are paid 80 cents on the dollar compared to their union counterparts. By the late 20th century, manufacturers, automakers and energy companies followed. In 1994, German automaker BMW opened a plant in Greer, S.C., where, as of 2016, only 1.6 percent of the workers were unionized.

The Thibodaux Massacre stands as a warning at a time when civil rights and economic gains are both receding. In 2016, black workers were the most unionized in the country, at 13 percent compared to 10.5 percent for white workers and less than 10 percent for Asian, Hispanic or Latino workers.

But union membership has tumbled across the board. Black unionization fell from 31.7 percent in 1983, as the Sun Belt labor market became the new normal. And the assault on unions come at a time when civil rights are under attack in the form of voter ID laws and the mainstreaming of white nationalism. The bullets fired at strikers 130 years ago are still fresh reminders that struggles for unity are more easily lost than won.