But their motivations and backgrounds have extensive overlaps. Both entered the military or government jobs during an era of massive hiring binges, controversial wars and repeated disclosures of alleged abuses by the U.S. military, the CIA and the NSA.
Both have said they wanted to call attention to abuses by the U.S. government, although critics have called them traitors who acted out of an exaggerated sense of self-importance.
Manning was gifted with computers and had begun learning the C++ programming language by the time he was 8. He never found a path to college and instead enlisted in the Army, where he was groomed for a career as an intelligence analyst.
Snowden’s plans to pursue a Special Forces career were derailed, he said, by leg injuries he sustained during training that ended his military stint after just three months.
It is less clear how Snowden came by his computer skills. But, as with Manning, his technology savvy appears to have helped him obtain a string of jobs that enabled him to snoop on and eventually steal sensitive files.
Their actions and motivations bear little resemblance to high-profile security breaches of the 1980s and ’90s. The best-known cases involved mid-career officials such as the CIA’s Aldrich Ames and the FBI’s Robert Hanssen, who were convicted of selling secrets to the Soviet and Russian governments for financial gain.
The closest parallel for Snowden and Manning may be Daniel Ellsberg, who in 1971 was the New York Times’ and The Washington Post’s source for the Pentagon Papers, a secret assessment of the Vietnam War that eroded the credibility of U.S. government’s more-optimistic public claims about the conflict. Ellsberg in recent days has praised Snowden and described the material Snowden disclosed as more significant than the documents he leaked four decades ago.
There are differences, however. Ellsberg was a senior military analyst working at the Pentagon who had a direct role in drafting the Pentagon Papers. The document was largely a record of U.S. decision-making rather than a blueprint of ongoing operations. Drafts were undoubtedly stored in safes, not on networks where they might be read by low-level employees at distant military or intelligence outposts.
A former senior NSA official recalled procedures in the 1970s that were archaic but secure. “When hot documents would go around they’d be in a double-sealed envelope, and some person would wait while you read it, re-
envelope it and leave,” the former official said. “By contrast, now you bring it up on your computer screen.”
Some U.S. officials question whether there is a generational gap in views on privacy and government transparency. Manning and Snowden, who are in their 20s, grew up with technology and the Internet as fixtures in their lives.
“We are recruiting Americans from a culture that has a deeper desire for absolute transparency than any previous cohort of people entering the service,” said Michael V. Hayden, former CIA and NSA director. “They are coming from a culture in which, for many, transparency is an absolute good, and it appears that in these two cases it influenced these people.”
Snowden appears to have left fewer online footprints than many of his generation, with no evidence of Facebook or Twitter accounts. In his comments to The Post, he indicated that was in part because of what he had learned.
The Internet “is a TV that watches you,” he said, a technology “governments are abusing . . . to extend their powers beyond what is necessary and appropriate.”
Ellen Nakashima contributed to this report.