THE BURNED OVER DISTRICT

Despite all the teeth gnashing, wailing and sack cloth & ashes about the Ed Snowden revelations, it appears that a traditional government leak to news agencies has cause the greatest disruption to US efforts to counter al-Qaeda.

Since news reports in early August revealed that the United States intercepted messages between Ayman al-Zawahri, who succeeded Osama bin Laden as the head of Al Qaeda, and Nasser al-Wuhayshi, the head of the Yemen-based Al Qaeda in the Arabian Peninsula, discussing an imminent terrorist attack, analysts have detected a sharp drop in the terrorists’ use of a major communications channel that the authorities were monitoring. Since August, senior American officials have been scrambling to find new ways to surveil the electronic messages and conversations of Al Qaeda’s leaders and operatives.

“The switches weren’t turned off, but there has been a real decrease in quality” of communications, said one United States official, who like others quoted spoke on the condition of anonymity to discuss intelligence programs.

The drop in message traffic after the communication intercepts contrasts with what analysts describe as a far more muted impact on counterterrorism efforts from the disclosures by Mr. Snowden of the broad capabilities of N.S.A. surveillance programs. Instead of terrorists moving away from electronic communications after those disclosures, analysts have detected terrorists mainly talking about the information that Mr. Snowden has disclosed....

McClatchy Newspapers first reported on the conversations between Mr. Zawahri and Mr. Wuhayshi on Aug. 4. Two days before that, The New York Times agreed to withhold the identities of the Qaeda leaders after senior American intelligence officials said the information could jeopardize their operations. After the government became aware of the McClatchy article, it dropped its objections to The Times’s publishing the same information, and the newspaper did so on Aug. 5.

The bad guys have known someone was listening for many years. After being spooked for awhile, they will return to the airways with some new tricks. Like a fisherman, the NSA has to be careful not to spook them again.