A trip to the Salvation Army store in Philadelphia shouldn't have put people's lives at risk. But on June 5, a building under demolition above the store collapsed, killing six victims. Union tradesmen at a construction project across the street from the collapsed building had called OSHA on four occasions to report safety violations at the demolition site. Rather than removing a brick wall from the top by hand, they reported, the contractor was destabilizing the wall from the bottom, threatening everyone below.

Toxicology reports revealed that the project's nonunion crane operator, who had a long arrest record, was under the influence of marijuana at work.

The blame game over this tragedy is playing out in the daily newspapers, which feature profiles of the victims, like 24-year-old Anne Bryan, a student at the Pennsylvania Academy of Fine Arts whose family described her as an "incredibly kind and loving person."

And the tragedy is spreading. On June 12, the city's building inspector in charge of overseeing the demolition project took his own life.

Central Salvage Co., a reputable union contractor, had bid on the demolition job, but the building owner, STB Investments, went on the cheap and decided to go with an unqualified nonunion contractor.

STB is owned by Richard Basciano, nicknamed New York Times Square's "Prince of Porn." Said to be worth $150 million, Basciano owned peep show stores in several cities that he held onto for years until increasing property values made them lucrative to sell or develop.

Concerned about the safety of others, the union workers across the street from the collapsed building sounded a warning that went unheard, with catastrophic consequences.

Another warning needs to be sounded. Our warning is to politicians and business owners who think that union members are "too expensive" and unions have "too much power," or who call us "thugs."

Our warning: Weaken or eliminate unions and workplace safety regulation at your own risk. More buildings will fall. More innocent victims will die. More families will mourn. And more employers will be sued. Our unions choose another future.

We recognize that the vast majority of contractors, union and nonunion are good, decent people. We will continue to reach out and organize. We will promote excellence on the job and protect the safety of workers and our communities. That's who we are.

Also: Hill: Defending Public Workers