screenshot It is still unclear how many Snowden stole and when he gave up access to them.

One of the fundamental disagreements between supporters and detractors of Edward Snowden comes down to a simple question:

Did Snowden take U.S. military documents not pertaining to surveillance?

On March 6, Chairman of the Joint Chiefs of Staff General Martin Dempsey told Congress:

“The vast majority of the documents that Snowden … exfiltrated from our highest levels of security … had nothing to do with exposing government oversight of domestic activities. The vast majority of those were related to our military capabilities, operations, tactics, techniques, and procedures.”

Snowden has denied any deliberate effort to gain access to any military information, stating: “They rely on a baseless premise, which is that I was after military information.”

Ben Wizner, Snowden’s legal advisor and primary spokesman, told Business Insider in an email that “the whole allegation is nonsense.”

The two sides clearly disagree on what is a basic yes-or-no question. One thing that is clear is that the NSA-trained hacker had the opportunity to gather and steal military information.

Snowden used an automated web crawling software to “scrape” the NSA’s systems, and the program was made especially powerful by his passwords as a systems administrator and passwords of colleagues.

Intelligence officials believe Snowden accessed or “touched” about 1.7 million files while helping to manage NSA computer systems in Hawaii. It’s unclear how many documents, pertaining to surveillance and otherwise, the 30-year-old ended up taking.

“There’s an ongoing debate in the [intelligence community] right now about what kinds of information did he touch, what did he take — what do we know?” Lt. Gen. Michael Flynn, Director of the Defence Intelligence Agency, told NPR.

When asked what Snowden could have taken, Lt. Gen. Flynn said: “All of the above. It’s intelligence abilities, it’s operational abilities, it’s technology, it’s weapons systems.”

Previously, Flynn told lawmakers: “Everything that he touched, we assume that he took.”

Wizner did not respond to a follow-up inquiries about Snowden allegedly “touching” military information.

The New York Times reported that Snowden “appears to have set the parameters for the searches, including which subjects to look for and how deeply to follow links to documents and other data on the N.S.A.’s internal networks.”

The unanswered question is critical.

“I’m concerned about defence capabilities that he may have stolen from where he worked, and does that knowledge then get into the hands of our adversaries,” Lt. Gen. Flynn, who server as the top military intelligence officer in Iraq and Afghanistan, told NPR.

If Snowden accessed and lifted military information, it could potentially endanger to American troops.

“All military combat operations depend on NSA contributions,” Robert Caruso, a former assistant command security manager in the Navy and consultant, told Business Insider. “[The Department of Defence] depends on NSA and the Defence Information Systems Agency to secure all its networks, and others networks too.”

For example, Flynn claimed that U.S. officals “know that there’s some evidence that [Snowden] may have gotten some information about” how the U.S. military defeats improvised explosive devices (IEDs). “And so we have to protect, you know, how we defeat these kind of devices. So we may need to change some of the way we operate.”

Caruso elaborated on Flynn’s example:

“If Snowden has information about how we combat the IED threat — even if he didn’t mean to take it — then it’s not a post-MRAP world or even are-MRAP world — it’s a future-American-casualties-that-could’ve-been-avoided world,” Caruso said. “It doesn’t matter what kind of armoured vehicle you have.”

It’s still unclear when Snowden gave up access to his full cache.

It appears that Snowden gave Greenwald and Poitras as many as 200,000 files, including about 20,000 Aussie signals intelligence files, 58,000 documents from Britain’s GCHQ intelligence agency, some file pertaining to Canada, and an unknown but substantial number of NSA files.

Beyond those documents, the NSA assumes that Snowden took as many as 1.5 million more documents (i.e., the other part of the 1.7 million he reportedly “touched”).

So how many NSA documents (if any) did Snowden take but did not give to journalists? And what happened to them?

Snowden told James Risen of The New York Times that he gave all of the classified documents he had taken from the NSA’s internal systems to the journalists he met in Hong Kong and kept no copies himself. However, there are clear issues with that claim.

On June 12, two days after he parted ways with Poitras and Greenwald, Snowden leaked specific details of NSA hacking targets in China and Hong Kong to the South China Morning Post. Snowden also told SCMP that he intended to leak more documents later.

“If I have time to go through this information, I would like to make it available to journalists in each country to make their own assessment,” he said.

Greenwald subsequently told The Daily Beast that Snowden had more NSA files than he gave to Greenwald and Poitras: “I believe he does. He was clear he did not want to give to journalists things he did not think should be published.”

Then, on July 14, three weeks after Snowden flew to Moscow, Greenwald told Associated Press that Snowden “is in possession of literally thousands of documents … that would allow somebody who read them to know exactly how the NSA does what it does, which would in turn allow them to evade that surveillance or replicate it.”

The U.S. believes Snowden’s cache also includes 31,000 documents that do not deal with NSA surveillance “but primarily with standard intelligence about other countries’ military capabilities, including weapons systems.”

Rick Ledgett, who heads the task force investigating Snowden’s raid on the NSA’s systems in Hawaii, told 60 Minutes that those files — some of the most closely held secrets by the United States — “would give [other countries] a roadmap of what we know, what we don’t know, and give them, implicitly, a way to protect their information from the U.S. intelligence community’s view.”

Significantly, Snowden has not explicitly denied taking documents not pertaining to surveillance. When asked follow-up questions, his lawyer pointed to the initial statement about Snowden not being “after” military intel.

And the leak of military intelligence, if Snowden has any, could “hinder future military operations,” Caruso said. “That is my fear, and in my view that position is not unfounded. We are talking the loss of our qualitative military edge, the possibility a future enemy on a future battlefield has advance knowledge of our tactics, techniques, and procedures.”

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