The congressional hearings on steroids have the potential to be one of the most important events in baseball’s long history. More important than any lockout or union strike. More important than the 1980s’ epidemic of cokehead players. You might have to go all the way back to the Black Sox scandal to find an event of equal meaning.

The reason is simple: The use of steroids, like the fixing of the 1919 World Series, goes directly to the integrity of baseball. Any time there is doubt about the final results, about wins and losses, batting averages and home runs, every player, every game is under suspicion. That’s where baseball is right now — under a huge, dark cloud.

Cleaning up this mess is not going to be pretty. Congressional hearings are blunt instruments. The truths that emerge often do so only after shameless grandstanding by politicians. Expect tiresome speeches dripping with sports cliches that have no purpose other than to get Rep. Joe Blow’s mug on TV.

That’s just the price of admission. The moment of truth will begin with an oath that will ask each player and baseball exec a simple question: Do you promise to tell the truth, the whole truth, and nothing but the truth? Right hands raised, they will answer yes.

Then, and only then, will we begin to learn the facts about steroids.

The commissioner, the owners, the union, the players don’t want us to know the truth. That’s why they’re kicking and screaming and their lawyer is pounding the table. Hot tip: Lawyers pound the table when they don’t have the facts or the law on their side.

The hysterical hell-no-we-won’t-go threats are a sure sign of how ugly the facts are. The revelations will be damaging, even devastating, to everybody involved. Who used steroids, who knew about it and when — all are likely to be laid bare. The cheaters and the liars will be exposed — on national television.

I say bring it on. Baseball has done everything it could to hide its dirty laundry. Even while players started bulking up like Popeye and home run balls took off like missiles, fans were told it was all because freaks like Barry Bonds and Mark McGwire had this wonderful “work ethic.” Bull poop.

Then, suddenly, after years of denying there was a steroid problem, baseball declared the problem solved. That’s like a consent decree where a crooked business denies it did anything wrong, but promises not to do it again.

That’s not good enough. Nor is baseball, which enjoys an anti-trust exemption and reaps billions from public stadiums and airwaves, wise to threaten a court fight over the hearings. That’s a fight it will lose, in public support if nothing else.

It’s never too late to be smart, and the smart move here is to be open and honest, if only to prevent the pols from taking over the issue. As one House member warned baseball, “If you don’t clean it up, we’re going to clean it up for you.”

Then, too, Congress has a weapon baseball can’t control: Jose Canseco. The angry former slugger can be counted on to repeat the admission in his book that he used the drugs and his sensational charges that many other players did, too.

Will those players — McGwire, Jason Giambi, Sammy Sosa, Rafael Palmeiro — dare refuse to testify after Canseco accuses them again? Under oath, on TV, will they deny they ever knowingly used steroids?

They’d be fools not to tell the truth. If they doubt it, they can ask Martha Stewart what happens when you lie to Uncle Sam.

— Michael Goodwin is a Pulitzer Prize-winning columnist for the New York Daily News.