For the second time in three years, a nation stands at the precipice — thanks to Big Labor.

At the end of 2008, two Detroit automakers were teetering, as well — companies whose out-of-control union benefits not only threatened their future but the larger U.S. economy, given the ripple effect that a GM failure would have had.

Unions played chicken, refusing significant concessions and daring President George W. Bush not to bail out Detroit. They had given enough, UAW boss Ron Gettelfinger said. The Republicans were trying to break the union, he pleaded to his Democratic allies. Then, as now, the real answer was breaking the union. Only with de-unionization could Detroit hope to compete in the long term against its nimbler, cheaper, foreign-transplant rivals.

But de-unionization did not happen. It could not, realistically — given labor’s history in the auto industry.

Today’s report that GM earned its first full-year’s profit since 2004 — $4.7 billion — is a reminder of the sacrifice the country had to make to maintain GM as a unionized company. Today’s profits come at taxpayer’s expense as Detroit trimmed its union costs (if not the power of the union) in return for an unprecedented government-led bankruptcy that allowed GM to shed all its bad assets.

What a deal. What company could not be profitable after such specialized treatment at the hands of the federal government?

That deal is not available to states like Wisconsin and Michigan today. Yet they face the same structural labor problems GM did. Standing on the precipice due to irresponsible collective bargaining, governors must make the hard choices that GM and Chrysler did not have to make. Not surprisingly, the press has forgotten — if it ever really understood — this lesson from the auto crisis.

Like the auto companies, the unions have outlived their purpose (indeed, in government they never had a purpose except to politically feed union dues to the Democratic Party, as Jonah Goldberg writes). Republican Scott Walker of Wisconsin is on the right track — union power must be scaled back for government to serve its citizens in a fiscally responsible way. But the sensible proposals of Goldberg — that unions in the public sector be abolished altogether — has about as good a chance as ending unionization of the Big Three.

And that does not bode well for America’s fiscal future.