We’ve yet to see the full impact of former National Security Agency contractor Edward Snowden’s unauthorized downloading of highly classified intelligence documents.

Among the roughly 1.7 million documents he walked away with — the vast majority of which have not been made public — are highly sensitive, specific intelligence reports, as well as current and historic requirements the White House has given the agency to guide its collection activities, according to a senior government official with knowledge of the situation.

The latter category involves about 2,000 unique taskings that can run to 20 pages each and give reasons for selective targeting to NSA collectors and analysts. These orders alone may run 31,500 pages.

If disclosed, that information would reveal vulnerabilities within U. S. intelligence gathering at the strategic level, the official said.

The Snowden documents that have been made public primarily involved the capabilities of NSA collection techniques and analytic systems, as well as partnerships with other governments and private parties. As damaging as those disclosures have been to operations, publication of past and current intelligence reports and requirements would be just as harmful, if not more so, to policymaking, the official said.

The first indications of Snowden’s haul being larger than previously thought came from Richard Ledgett, the NSA official leading the investigating task force, from interviews he gave last week that were published Friday by Reuters and aired Sunday on CBS’s “60 Minutes.”

Ledgett, whom Reuters described as a 36-year intelligence veteran who may be the NSA’s next deputy director, told the news agency that the leaked tasking documents “make me nervous because they reveal what we know and what we don’t know, and they are almost a road map for adversaries.”

On “60 Minutes” he said the “road map” would show “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.” In short, he called that set of documents “the keys to the kingdom.”

Where the copies of these sensitive tasking documents are is an unanswered question.

Snowden, in Hong Kong, distributed NSA documents during the first week in Juneto three journalists — Glenn Greenwald, documentary filmmaker Laura Poitras and Barton Gellman. Gellman’s stories based on them have been published in The Washington Post.

Snowden went public June 9, after the first stories appeared. Then he went into hiding.

On June 24, the South China Morning Post published a story based on a June 12 interview with Snowden in which he indicated that he had more documents to leak. “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, independent of my bias, as to whether or not the knowledge of U.S. network operations against their people should be published,” Snowden was quoted as saying.

On July 14, the Associated Press published a story in which Greenwald said that Snowden — then in Moscow at the airport — had “literally thousands of documents” that constitute “basically the instruction manual for how the NSA is built.” Greenwald, who said he had spoken to Snowden hours earlier, told the AP that in order to prove his credibility Snowden “had to take ones that included very sensitive, detailed blueprints of how the NSA does what they do.”

These documents, Greenwald said, “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.”

But, Greenwald added, Snowden had insisted they not be made public. On July 19, Greenwald told German public broadcaster ARD that Snowden in June in Hong Kong had given him and Poitras about 9,000 to 10,000 top-secret documents.

On Oct. 17, the New York Times’ James Risen published a story based on an interview with Snowden in which he said he did not take any NSA documents with him to Russia, where he now has a year-long residency permit.

Greenwald recently told ABC News, “We published only a small fraction of the ones that we have been given so far because we have gone through each of them and made sure that nothing we are publishing endangers human lives.”

Still, there are “a lot of very significant stories that are yet to be reported,” he said during an interview for an ABC News special to be aired this month.

So where are the tasking documents? I’ve not asked Gellman, Greenwald or Poitras because were I in their positions I would not say one way or the other.

The NSA’s Ledgett considers them so important that the security of those documents is worth having a discussion with Snowden about amnesty.

“My personal view is, yes, it’s worth having a conversation about. I would need assurances that the remainder of the data could be secured, and my bar for those assurances would be very high,” Ledgett said.

That was not the view of Ledgett’s boss, Gen. Keith Alexander, the NSA director.

Asked on “60 Minutes” about making such a deal, Alexander said, “This is analogous to a hostage-taker taking 50 people hostage, shooting 10 and then saying, ‘If you give me full amnesty I’ll let the other 40 go.’ ”

Alexander insisted that people “have to be held accountable for their actions . . . because what we don’t want is the next person to do the same thing — race off to Hong Kong and to Moscow with another set of data knowing they can strike the same deal.”

That’s the dilemma. In an age of computers, electronic tablets and cellphones, protection of seriously classified information will only get more difficult.

For previous columns, go to washingtonpost.com/fedpage.