The NSA's claim about how surveillance programs have thwarted terrorists ("Programs disrupted 50 plots, NSA says," June 19) warrants further scrutiny as does the claim by Rep. Dutch Ruppersberger that the leaker did "tremendous damage."

On the matter of 50 plots being thwarted, the specifics should be revealed to the public. Were these "plots" significant, or do they include planned civil disobedience by the Occupy movement or tea party? Was this NSA program necessary in each of the supposed 50 plots? Recent reporting has revealed that a similarly cited plot was actually exposed by unrelated, narrowly targeted surveillance.

On the matter of "tremendous damage" by the revelations, I'm reminded of President Richard Nixon's secret wars in Cambodia and Laos. Exposure of these secret wars were not revelations to Russia or communists in Southeast Asia; the government was keeping these wars secret from American citizens.

Potential terrorists who are of any significant threat surely know about NSA capabilities, which have been trickling out for many years. We deserve some specifics from Mr. Ruppersberger about what he means by "tremendous damage."

The Sun has a duty to investigate these claims more closely, but there are three barriers to doing that. First, the establishment is circling its wagons to suppress legitimate probes of government excesses. The Sun editorial board needs to resist succumbing to the establishment group-think that has proven so damaging in the past.

Second, the NSA program in question is possibly being used to identify sources that The Sun would need to gain background, let alone information to publish. This NSA program is having a chilling effect on both sources and journalists, leading to self censorship.

Finally, the capacity to conduct investigative reporting has withered over the past decade. According to recent reporting by the Associated Press, "Newsroom employment at newspapers is down 30 percent since a peak in 2000 and has gone below 40,000 people for the first time since 1978."

Hopefully these barriers will not thwart good journalism on this issue. The findings of the 1975-76 Church Committee Senate hearings into government intelligence abuses should motivate newsrooms across the Country to take a skeptical look at claims like those being made by the NSA and Mr. Ruppersberger.

Jim George, Baltimore