The centenary of a 1911 fire that killed 146 New York garment workers and triggered historic changes to U.S. labor laws is being marked this week as unions once again battle for their lives.
The Triangle Shirtwaist fire, named after the burning of the Triangle Waist Company factory in Manhattan, was a tragedy that immediately resonated beyond the horrific mass deaths.
New York — then, as now, an immigrant-based city — was used to tough working conditions, but there was public fury at revelations that the mostly female and often young victims died because employers ignored basic safety.
There were no automatic water sprinklers, doors apparently swung the wrong way and the shoddily built exterior fire escape collapsed under the weight of panicking employees.
Most cruelly, a crucial staircase that was locked as part of antitheft measures by the owners turned the building into a death trap.
The fire department promptly arrived, but their ladders and hoses could not reach further than the seventh floor.
The fire had started on the eighth floor and leapt to the 10th, leaving those on the ninth floor to die in the building or leap to their deaths on the sidewalk below.
This week's commemoration will be marked by an HBO documentary, a 40-hour fast by union workers, lectures and a big procession at the site — now part of New York University — on March 25, the anniversary.
The accident was one of the worst of the Industrial Revolution, but the resulting outcry triggered historic new worker protection laws in New York state and then across the country.
Union historians see the dead in the Triangle fire as having achieved a victory that until then had eluded the living.
But there is added tension to commemorations this year as unions in Wisconsin and other politically important states battle attempts by Republican-led state governments to significantly roll back their power.
"Given the attack on public sector unions, there's a unique importance to the centenary this year," said Harley Shaiken, a professor at the University of California, Berkeley, who specializes in labor issues.
"The Triangle fire underscores not only where unions came from but that you urgently need the checks and balances of groups representing workers," he said.
Ruth Milkman, a sociologist at City University of New York, said the 1911 tragedy ushered in a "golden age" of government regulation in the workplace that forced employers to be mindful of safety and other basic rights.
That age began to end in the mid-1970s, she said. Today just 6.9 percent of private sector workers and 36.2 percent of public employees belong to unions.
"Since '75 those things in many ways have unraveled, and we're going back to those days," she said.
"Today the main parallel is the role of immigrants in the workforce.... Low-wage workers in the worst jobs are overwhelmingly foreign-born and many do work in dangerous conditions, just as (Triangle workers) did."
Unions have a long history in the world's largest economy, but beyond the easily visible workforce an enormous shadow population of Asian and Latin American immigrants often work in harsh conditions for little pay.
The garment industry in Los Angeles is regularly cited as a chief offender, with some 67 percent of factories there violating minimum wage and overtime laws, according to studies cited by Cornell University.
However, with the country inching out of a devastating recession and buried in debt, the Republican Party's message of breaking unions in order to slash budgets resonates with some voters.
Seizing on major gains in November elections and eyeing next year's presidential race, Republicans in 37 states are pushing legislation to restrict bargaining rights and the ability of unions to collect dues and retain members.
However, it's not just about balancing budgets. Unions are also the biggest source of financial and grassroots, get-out-the-vote organizational support for Democrats and have long been a target of business-backed Republicans.
The fate of unions is likely to be a source of conflict in the run-up to the 2012 presidential election, with Democrats trying to protect a key reservoir of support and Republicans hoping to drain it.
"It's very clear at this point that the motivation of the attack on public sector unions is overwhelmingly political, not fiscal," Shaiken said.
"We're going to see this on an ongoing basis for the next two years. It could prove a critical factor in 2012."