BILL MOYERS: As we speak, the Democrats are on their way home from Denver in time for Labor Day weekend. That's a special holiday for many of them — especially the thousand or more delegates who are either active or retired members of a union, or from households with union members. Organized labor has been wandering in the wilderness for some years now, and its leaders came out in force in Denver, proclaiming: "We're back!"

GERALD MCENTEE: We have been tattooed, beaten, bruised, thrown up against walls for the last eight years!

BILL MOYERS: Last Sunday, they held a big rally for Obama, calling on him to make union organizing a priority if the Democrats take the White House. And at the convention itself, sprinkled among the prime-time speakers were some heartfelt, personal stories from union workers including autoworker Robin Golden from Michigan.

ROBIN GOLDEN: In two weeks, I'll be unemployed. My job is being shipped to Mexico, along with the jobs of most of my 430 co-workers. That means every single member of my local union will be unemployed in two weeks.

BILL MOYERS: In past decades, the voices of the labor movement swelled the Democratic chorus. Then, Democratic presidential candidates officially opened their campaigns in the city that was the symbolic heart of union country — Detroit, then the engine of the booming auto industry. Standing in Cadillac Square on Labor Day was a Democrat's way of saying our hearts are one.

JOHN F. KENNEDY: I have come here today on a day that belongs to the working men and women of America...

BILL MOYERS: John Kennedy kicked of his campaign for president in Cadillac Square in 1960, praising unions that fought for education, for better health care, even for family farms. Kennedy declared that as unions go, so goes America.

JOHN F. KENNEDY: We share a common, deep-seated belief in the workings of free collective bargaining and in the growth of free, responsible unions, and, unlike our opponents, we don't just believe that on Labor Day.

BILL MOYERS: These were the golden years for organized labor. Union bargaining power helped lift other worker's boats — and the yachts of their employers — in a rising tide of prosperity that moved millions of families into the middle class.

But that seems now another age, another world. Union membership has plummeted from Kennedy's day — down to less than 8% of the private sector workforce. Millions of union jobs have been lost to cheap labor abroad, and to consumers who demand cheaper prices. Corporations have warred relentlessly on unions, in league with a conservative movement that regards business as its own ATM machine. Collusion between government and corporations in the global economy has left workers to fend for themselves. The results have been disastrous.

Job security — slashed. Pensions — slashed. Healthcare benefits — slashed. In a golden age of profit-taking and extravagant wealth for CEOs, compensation for employees, as a share of the total economy, has reached a new low.

And even with the Democratic party, labor's place at the table cannot be taken for granted. President Bill Clinton, after all, championed NAFTA, the trade deal that sent manufacturing jobs overseas. Barack Obama has wavered on his opposition to reopening NAFTA. Democrats in Congress are being inundated with money from corporations. And in Denver this week, those same corporations were hosting lavish parties — captured here by ABC News' Investigative Unit — shelling out millions to wine and dine Democratic officials.

BRIAN ROSS: "Lobbyists gone wild!"

BILL MOYERS: A house divided can hardly be called the home of working people. So for all the rhetoric and cheer in Denver, workers have little to celebrate this Labor Day — they've been falling farther behind for years now. But across the country, there are growing signs of defiance:

You see it as California nurses pushed for universal health care. You see it as workers march in Los Angeles for a living wage. You see it in immigrants fighting back against a system that hires them to pick and prepare our food, yet pays them pitiful wages and treats them as criminals.

It just might be that that same spirit of anger roused by injustice, that old and enduring hunger of working men and women for a better deal. It just might be the spark that catches fire, lighting the way once again for politicians returning to Cadillac Square on Labor Day.

That's it for the Journal. We'll see you again next week. I'm Bill Moyers.