"We ask them to share any specific national security concerns that would result from those disclosures," she said.
Sometimes officials respond with redaction requests, the Guardian said, but often the paper has already made its own decisions about redactions of obviously sensitive operational details or people's names that shouldn't be published, Gibson said.
Some other theories floating around about how the paper decides to publish leaks are bogus, the editor said. "Obviously we try and make sure each story has as much impact as possible, but we tend to publish when we've found a story, worked it up to our satisfaction, determined that it's in the public interest, and it's ready," she said.
There are several circumstances under which The Guardian would not publish a story. Speaking personally, Greenwald said he would not publish documents that could help other states learn how to better spy on their own citizens. Also not to be published: the names of covert agents, the names of agency employees who are not high-ranking officials and documents that could unfairly defame someone, he said.
One question is the extent to which the revelations surrounding the NSA have constituted actual illegal activity. The journalists were asked to address this, and whether there would be more "smoking guns" providing undeniable proof that the government has broken specific laws.
"I think there already are things clearly showing the government broke the law, including the Constitution," Greenwald said.
Some previously classified documents have shown that the NSA has operated illegally in certain cases. In August a 2011 court ruling from the Foreign Intelligence Surveillance Court was made public, saying that the way the NSA collected data violated the Fourth Amendment.
Despite multiple disclosures, some readers seem indifferent, apparently already having assumed that the government monitors citizens' communications as part of counterterrorism efforts. That response, The Guardian's Gibson said, is baffling.
"It's inexplicable, given the number of administration voices all welcoming the debate and acknowledging it would not have happened without Edward Snowden," she said.
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