Finally, the world is safe from Judith Miller.

With her locked up in the same maximum-security prison as would-be Sept. 11 terrorist Zacarias Moussaoui, we no longer have to worry that a 57-year-old New York Times reporter is out there blatantly interviewing people.

As she was taken away last week, Miller is said to have wondered how it ever came to this. It’s simple, really.

Two years ago, she didn’t write a story.

The story she didn’t write did not out Valerie Plame, a covert operative of the Central Intelligence Agency. Miller got Plame’s name from a source who spoke on condition of anonymity.

About the time Miller was not using that information, columnist Robert Novak was. He wrote that “two senior administration officials” told him Plame was a spy. Because Plame’s husband is former Ambassador Joseph Wilson IV, who was vocal in his criticism of the decision to invade Iraq, a few of us smelled payback – Plame’s career wrecked in retaliation for her spouse’s outspokenness.

If true, it represented politics at its most thuggish. It may also have represented a breach of the law that makes it a felony to reveal the name of a covert operative. Investigators looking into the leak have not focused on Novak, leading to speculation that he cooperated with prosecutors.

Miller, by contrast, defied a federal judge’s order to reveal her source. She is in prison for refusing to break her word.

Some observers say that’s just desserts for a woman they feel helped pave the way to war with credulous reporting on weapons of mass destruction. But Miller is not the point. Rather, the point is media’s ability to fulfill its role as a watchdog of government.

Others accuse Miller of placing herself above the law. But she’s not flouting the law, she’s affirming the right of civil disobedience – refusal to obey unjust statutes and willingness to pay the price for doing so. This was the principle behind the civil rights movement. And the Pentagon Papers case. And numberless anti-abortion demonstrations.

Still others fault Miller for shielding a lawbreaker. While I have zero sympathy for whoever outed Valerie Plame, the fact is that people who whisper secrets to reporters are often lawbreakers, if only for telling the secrets. So that can hardly be the standard.

Bottom line: In an era when news outlets are pilloried for being too liberal conservative untrustworthy irrelevant, Miller’s martyrdom – it is not too strong a word – is a stirring reminder that media have a vital mission: Ferret out the truth and tell it, even at professional or personal risk.

Sometimes fulfilling that mandate requires promising anonymity to those who fear to speak otherwise. If reporters cannot keep that promise, reporters cannot do their jobs. And we are all poorer for it.

That’s why most states have laws making communication between reporters and sources privileged. Congress should immediately enact a similar statute on the federal level.

Still, the most troubling question here involves not a reporter’s ethics but the administration’s.

This week, Newsweek reported that it had unearthed e-mails between Karl Rove and a Time magazine reporter in which Rove, the president’s chief political adviser, referred to Plame, albeit not by name. President Bush, who had previously vowed to fire whoever outed Plame, declined to repeat the pledge in the wake of that revelation. His chief spokesman suffered a similar case of mush mouth.

Rove’s e-mails are not the proverbial smoking gun. But they give heft to suspicions that Plame was the victim of a political mugging that teeters close to treason. Given that this White House has repeatedly charted new depths of character assassination against its critics, those suspicions don’t seem farfetched.

But at least we’re protected from Judith Miller.