He makes a concealed reference to the reporters in the Wen Ho Lee case, who are protecting government sources that apparently felt the government's normal powers of subpoena and arrest were insufficient, and decided to try Dr. Lee in the press.
A free and inquiring press can be a check on government power, or an extension of it - the Wen Ho Lee case does not look like an example of the sort of leak we ought to be protecting.
MORE: As to the Plame case, I agreed with the NY Times before they did - I doubt there is a criminal case here. However, I fail to see why we should be worried about protecting the right of Adminstration officials to put their stories forward anonymously - it is not as if the White House currently lacks for power.
That said, a cogent theory of the information flow in the Plame leak was provided by Cecil Turner in a comment at the Beldar blog - briefly, a State Dept. / INR fellow met both Valerie and Joe at the fateful meeting where Ambassador Wilson was selected to go to Niger. He later presented this connection for the edification and education of the curious higher-ups in State who wondered who this Joe Wilson was, and why he was writing in, and leaking to, the Times. Regrettably, the INR staffer had not been apprised of Ms. Plame's covert past, and here we are.
MORE: Kevin Drum makes the case for a reporter shield law; Mark Kleiman tells us that "I'm not against some protections for the newsgathering process, but I think a generalized "reporter-source privilege" goes way too far". Mr. Kleiman also buries William Safire - I embrace his spirit, although I would dispute some of his assertions.