The worst job I ever had came one summer as a teenager when I worked as a clerk for a New Jersey company that made wristwatch parts.

The tedious work of crafting these tiny parts was done by an almost all-female workforce. They were paid by how many pieces they could produce in a day. My job was to weigh the finished products and calculate how many pieces they had turned in.

The environment was nasty and self-defeating. Management had pegged the pay to quotas that the women were expected to meet. However, a few women, who were faster and greedier than the others, would push the pace of work to make more money.

But then the managers would simply set the quotas higher and lower the rate of pay per part produced. No matter how hard they worked, the women always lost.

I thought back to that brutish summer on the factory floor while reading David Von Drehle's remarkable book, Triangle: The Fire That Changed America.

Von Drehle writes about an even more vulnerable and exploited group of workers, immigrant women working in the shirtwaist factories of New York City shortly after the turn of the 20th century. Like the wristwatch workers, these women were doing piece work handcrafting parts of fine garments. The difference, however, is how these women fought to unionize against all the odds. And in the end, they won, at the cost of a terrible tragedy.

Triangle begins against the backdrop of a city teeming with immigrants who are crammed into tenement buildings performing piecework in their homes day and night.

Two of those exploited workers, Max Blanck and Isaac Harris, pull themselves up enough to form their own garment business, the Triangle Waist Company, located in the upper floors of a factory building in New York's Greenwich Village.

However, the once-exploited workers prove to be even more ruthless as owners. Von Drehle shows how they hired street thugs to beat up women who were organizing the union.

He demonstrates how they skirted all manner of safety violations in their factories and, concerned that one woman had stolen some fabric, insisted that all but one exit to the factory be locked at closing time.

They were also the leading advocates in breaking a citywide strike by garment workers that serves as this book's opening act.

All of this leads up to the awful events of March 25, 1911, when a stray flame in one of the fabric bins grew within three minutes into a ferocious inferno. Finding themselves locked into the factory floors, many of the workers died by plunging to their deaths on the streets below as firefighters and a crowd watched in horror. A total of 146 people died that day, 123 of them women.

For its time, the Triangle Fire had the same cataclysmic impact on New York City as the World Trade Center attacks had on New York today. And like "9/11," the principal architects of the disaster got away.

Although they were tried for their role in the fire, a jury acquitted Blanck and Harris. Von Drehle shows how they actually made money on the fire. They had carried a surplus of insurance on the building, which had been subject to some earlier smaller fires. For each dead worker, the owners got about $400 in return. They also managed to avoid any civil verdicts in the fire.

One hopes there is a special circle in hell for such men - and that all the doors are locked.

Von Drehle recreates this period with complete mastery. He builds his story upon an earlier work by Leon Stein, a union man who interviewed many of the survivors for his 1962 book, The Triangle Fire.

Besides bringing many of these characters to life, Von Drehle shows how pivotal the fire proved to be in the history of labor unions and in the rise of urban liberalism.

He shows how a Tammany Hall appointee named Al Smith broke from the mold of old-style machine politician to create real reform for the people who would elect him governor of New York several years later.

And he makes a convincing case for the rise of urban liberalism from the ashes of that all-consuming fire.

One of the witnesses to the blaze that day was a young woman named Frances Perkins, who had been a budding political activist in 1911. Perkins would later become Labor Secretary under President Franklin D. Roosevelt, the first woman to hold that job.

Years later, she would say that The New Deal began the day of the Triangle Shirtwaist Fire.

John C. Ensslin is a staff writer at the Rocky Mountain News.