As the intelligence community continues its assessment of the damage caused by Edward Snowden’s leaks of secret programs, Director of National Intelligence James Clapper says it appears the impact may be less than once feared because “it doesn’t look like he [Snowden] took as much” as first thought.

“We’re still investigating, but we think that a lot of what he looked at, he couldn’t pull down,” Clapper said in a rare interview at his headquarters Tuesday. “Some things we thought he got he apparently didn’t.” Although somewhat less than expected, the damage is still “profound,” he said.

This assessment contrasts with the initial view in which officials, unsure of what Snowden had taken, assumed the worst — including the possibility that he had compromised the communications networks that make up the military’s command and control system. Officials now think that dire forecast may have been too extreme.

It’s impossible to assess independently the accuracy of what Clapper said, either about the damage Snowden allegedly caused or its mitigation. That’s one reason why a legal resolution of the case would be so valuable: It would establish the facts.

In the damage evaluation, the intelligence community has established three tiers of material: The first tier is the 300 or so documents that a senior intelligence official said news organizations in the United States or overseas have already published, often with redactions. The second is an additional 200,000 documents the United States believes Snowden or his associates gave to the media.

It’s a third tier of documents, which Snowden is assumed to have taken but whose current status isn’t known, for which officials have lowered the threat assessment. This batch of probably downloaded material is about 1.5 million documents, the senior official said. That’s below an earlier estimate of 1.77 million documents.

In the months immediately after June 2013, when Snowden began to reveal his cache of National Security Agency documents, U.S. officials said they couldn’t be sure what he had seen and downloaded. Now, by piecing together a replication of top-secret files at the time, they have a better idea of what Snowden may have taken.

In Snowden’s recent interview with NBC News’s Brian Williams, the former NSA contractor seemed eager to explore a deal that would allow him to return to the United States and face legal proceedings with some sort of negotiated plea agreement.

A senior intelligence official cautioned that any discussion of plea negotiations would be overseen by the Justice Department. He said the comment by NSA Deputy Director Rick Ledgett that there was “room for discussions” with Snowden reflected Ledgett’s personal views only.

“Plea negotiations are difficult if you start by saying you’re a hero and wanting a parade,” the senior official said, dismissing Snowden’s characterization of his actions during the NBC News interview as patriotic and constitutional. The intelligence community sharply disagrees with that self-assessment.

But the door still appears to be open for Snowden to negotiate some process under which he would return to the United States from Russia and face charges. “If he came back and told everything he knows, then perhaps some accommodation could be reached,” the senior official said.

The official said that in the event there were plea discussions, there could be a wide range of potential outcomes depending on Snowden’s inclination to cooperate and share information.

Pressed to explain what damage Snowden’s revelations had done, the official was guarded, saying that there was “damage in foreign relations” and that the leaks had “poisoned [NSA’s] relations with commercial providers.” He also said that terrorist groups had carefully studied the disclosures, turning more to anonymizers, encryption and use of couriers to shield communications.

The senior official wouldn’t respond to repeated questions about whether the intelligence community has noted any changes in behavior by either the Russian or Chinese governments, in possible response to information they may have gleaned from Snowden’s revelations.

The official said the director of national intelligence is developing new procedures to make a future breach of secrecy less likely, including “continuous evaluation” of those with high security clearances that would monitor their use of social media and other online activity. But he said he worried that such a regime might be “oppressive” and that employees might decide it was “too hard to work with.”

Clapper’s interview illustrates one unlikely benefit of the Snowden affair, which is that officials have decided to be more transparent in discussing intelligence issues. That, at least, is a step forward.

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