Journalists have a professional commitment to the idea that more debate is better, so we instinctively side with leakers. But I’m skeptical about some of the claims of Edward Snowden, the young National Security Agency contractor who leaked secrets about that agency’s surveillance programs to The Post and the Guardian.

Snowden has described his actions in idealistic terms. “I’m willing to sacrifice . . . because I can’t in good conscience allow the U.S. government to destroy privacy, Internet freedom and basic liberties,” he said in an interview with the Guardian. But it’s hard for me to see him as a hero.

What worries me is that Snowden is challenging the rule of law. The NSA Internet surveillance program he decided to reveal is legal, in the sense that it was passed by both houses of Congress and is reviewed regularly by the intelligence committees. It is overseen by judges who sit on the Foreign Intelligence Surveillance Court. In 2008, that court ruled against a company that challenged the law.

Perhaps Snowden would argue that Congress and the courts ­haven’t been aggressive or diligent enough in their oversight, and that the NSA has dangerously misused its surveillance authority. Or maybe he would argue that he’s answering to a higher moral code, or that Congress and the courts are wrongly interpreting the Constitution. These claims will be tested in the coming debate, but we should be wary about endorsing any contention that it’s okay to violate laws because you’re acting on higher authority.

Snowden’s case is similar to that of CIA dissident Philip Agee. He published a revelatory memoir in 1975 called “Inside the Company: CIA Diary,” which outed the names and code names of scores of operatives with whom Agee had worked. He wrote in the introduction: “When I joined the CIA I believed in the need for its existence. After 12 years with the agency, I finally understood how much suffering it was causing. . . . I couldn’t sit by and do nothing.” Agee died in 2008 in Cuba, where he had sought refuge.

The CIA claimed at the time that it had suffered great damage from Agee’s revelations, but it’s still very much in business. Indeed, you could argue that the agency is far more aggressive and willing to use deadly force today than Agee ever envisioned. In that sense, we should be skeptical both of the efficacy of whistleblowers and of claims that unauthorized disclosures (as by Agee, or now Snowden) will cause irreparable harm. Usually these turn out to be overstated.

James Clapper, the director of national intelligence who oversees the NSA, argued last weekend that Snowden made “reckless” disclosures about its monitoring of foreign Internet communications, and that “potentially long-lasting and irreversible harm” could come from the revelation of a court order authorizing collection of telephone call data from Verizon. Congress and the courts will examine such claims, but how should we as citizens evaluate them?

My guess is that Clapper is correct when he implicitly argues that these electronic surveillance programs are the United States’ best tool in combating terrorism. It’s probably also true that each revelation of U.S. capabilities weakens this advantage by putting adversaries such as al-Qaeda on notice about our snooping capabilities. The revelations likely make it harder, as well, for U.S. corporations and foreign allies to cooperate.

For evidence of how al-Qaeda goes to school on leaks about surveillance techniques, just read the collected messages of Osama bin Laden that were taken from his hideout in Abbottabad when he was killed May 2, 2011. He admonished his aides how to avoid U.S. overhead surveillance (“move only when the clouds are heavy”) and money-laundering surveillance (“get rid of the bag that the money was in because it might have a chip”).

What bin Laden understood best was the need to avoid NSA monitoring of his telephone and Internet communications. He went dark, communicating only by courier. That’s how he remained hidden in plain sight for five years: He didn’t leave any digital tracks.

Some might argue that the bin Laden case shows that the NSA’s efforts are futile; the terrorists have gotten too smart for us. But intelligence collection relies on the human fact that even smart people do stupid things; they forget how powerful and pervasive the U.S. systems are. That’s why these surveillance programs remain valuable.

The United States went security-mad after Sept. 11, 2001, in ways that harmed the country. But these excesses led Congress to restructure surveillance programs so that they were lawful and controlled. These lawful programs were the ones Snowden unilaterally disclosed.

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