David Corn offers a preview of how the argument over Mary McCarthy is likely to take shape. He writes:

As facts emerge slowly, I’ll be following this closely–especially since I expect the partisans on the right to argue that anyone who wanted Libby or Roe prosecuted for leaking (vis a vis Valerie Wilson) should call for the same in this case. Not necessarily, for as the White House said recently, there are good leaks and bad leaks. And leaking about CIA abuses is not the same as leaking to discredit a policy critic.

Me: He’s got a point, of course. But it does cut both ways. “Leaking” — quotation marks necessary because Bush didn’t technically leak so much as declassify information — to “discredit” someone (Joe Wilson) who is distorting the facts is different from a CIA agent deliberately revealing classified information in violation of the law. To be sure, one is free to make the “greater good” argument — as Corn is clearly inclined to do — but that doesn’t automatically make it a winning argument. Indeed, it ultimately boils down to saying “leaks I like are justified even when blatantly illegal.”