And comments powerfully on the case of James Rosen:

A FREE press in a democracy demands a delicate balance. The First Amendment means the media must have the right to inquire without hindrance. The government has a legitimate interest in keeping some national security information secret. When these come into conflict, the balance often has been struck this way: The media are free to pursue secrets, but it is up to those in government to keep them. When the media come into possession of information that, if disclosed, could be damaging, the government can plead the case for secrecy — and the media generally are open to persuasion.

Up to now, there have been no prosecutions of reporters under the 1917 Espionage Act, a reflection of this balance in action.

The balance has been upset by an affidavit filed by the FBI in a criminal investigation into a national security leak. Special Agent Reginald B. Reyes asked a court to grant a search warrant for the e-mails of a reporter, James Rosen, the chief Washington correspondent of Fox News, on grounds that Mr. Rosen is a “co-conspirator and/or aider and abettor” of the leak of classified information. The target of the criminal probe is Stephen Jin-Woo Kim, who in 2009, when the leak occurred, was a State Department arms expert with a security clearance. The leak concerned intelligence information about North Korea.

What did the journalist do to become a potential criminal co-conspirator? According to the FBI agent, he “asked, solicited and encouraged” his source to disclose sensitive information. The reporter did this “by employing flattery” and playing to the “vanity and ego” of Mr. Kim. In other words, the journalist was doing what reporters do. Unfortunately, a judge signed off on this flimsy search warrant.

So did the attorney general of the United States.