YOU’VE been hearing all about Alan Hevesi’s feud with Rudy Giuliani – how the comptroller and mayoral candidate says that he’s become the target of Rudy’s wrath because he dared to expose fraud at City Hall.

You might have noticed that Hevesi doesn’t reveal the subject of his supposedly brave and fearless inquiry.

That’s because he doesn’t want you to know the details.

The fight Hevesi picked with Rudy last year had to do with Giuliani’s management of one of the great success stories of this or any other mayoralty in this or any other city in this or any other century.

And make no mistake: Hevesi picked the fight in the first place because he was preparing his own run for mayor and needed to get in good with some of the most reactionary forces in the city.

The subject of the fight: welfare reform.

More than 600,000 New Yorkers have left welfare since the passage in 1996 of federal legislation ending the lifelong right to public assistance – and there has been no uptick in indigence, shelter or soup-kitchen use in the years since. Indeed, unemployment in New York City has dropped.

Can you blame Alan Hevesi for wanting to keep from you the information that he was working against Rudy’s remarkable accomplishments in the area of welfare reform?

What happened was this. Opponents of the mayor’s aggressive welfare-to-work efforts were frustrated by the fact that the disasters they predicted in the aftermath of the 1996 federal law ending the lifelong right to public assistance did not take place. So, because they could not tar the Giuliani administration with having turned New York into a new Calcutta, they decided to try an ethical smear instead.

In particular, they tried to target Rudy’s visionary human-resources administrator, Jason Turner – a much-hated figure among the urban left because he had brilliantly and aggressively managed the nation’s most far-reaching welfare-reform effort in the state of Wisconsin.

The tale is immensely complicated, but basically it boils down to this. Turner was hired – and New Yorkers are lucky he was hired – because he possessed expertise in an area that almost nobody in the country had any hands-on experience with.

Turner and Rudy decided they were going to turn the city’s welfare offices into job centers – so that welfare recipients would know where to go, whom to talk to and what to do when their benefits ran out for good and they needed gainful employment.

Turner believed the company that could best help in this regard was the one that had done the same work in the city of Milwaukee, called Maximus. He made no bones about attempting to steer the job Maximus’ way – which makes total sense, given how little experience anyone had had with these efforts and just how massive a job it was to institute these reforms in the largest city in the country.

Critics cried foul: Turner and the administration were violating competitive bidding rules. Nonsense, said the administration and Turner: They were employing an expedited process to get the job done, which allowed them to circumvent some of the more time-consuming rules on how to bid for government work.

Enter Alan Hevesi, then laying the groundwork for his mayoral run. The comptroller feared that in the Democratic Party he was considered a Giuliani lackey. What better way to demonstrate his independence, and to send winks and nods in the direction of the anti-welfare-reform forces, than to try and hold up the contract with Maximus?

So he did. And in April 2000, Hevesi got a judge to agree with him on holding it up. Seven months later, that judge was overturned by the New York State Court of Appeals, which ruled that Hevesi had overstepped his bounds and that the City Charter gave the mayor the right to do what he did.

Alan Hevesi threw in his lot with the enemies of reform and was slapped down. But again, he doesn’t want you to know this because he wants those of you who think he’s a moderate successor to the mayor to vote for him on Sept. 11.

Here’s a piece of advice: Don’t.

E-mail: podhoretz@nypost.com