Bradley Manning, a 25-year-old Army intelligence analyst, was convicted last week of nearly all but the most serious charge of treason for leaking classified documents to WikiLeaks. But his trial still hasn’t resolved how much damage, if any, those leaks have done.

That’s the key question in Manning’s sentencing hearing, which began last week. U.S. officials now have a chance to detail what impact the leaks have had on their operations before a judge determines how much time Manning will serve.

Manning faced a maximum of 136 years, although on Tuesday the judge granted a request by the defense to combine some sentences, bringing his maximum penalty down to 90 years.

In the past, officials have said that his leaks caused “substantial” damage, without specifying what or how. In 2011, Reuters reported that several internal U.S. government reviews showed that while the leaks were embarrassing, they weren’t significantly damaging. Most of the embassy cables, for example, revealed that U.S. officials said in private more or less what they said publicly — if a little less delicately worded.

Former Defense Secretary Robert Gates told reporters in 2010 that official concerns about the leaks were “fairly significantly overwrought”:

“The fact is governments deal with the United States because its in their interest, not because they like us, not because they trust us and not because they believe we can keep secrets,” he said. “Some governments deal with us because they fear us, some because they respect us, most because they need us. We are still essentially …. the indispensable nation.”

“So other nations will continue to deal with us. They will continue to work with us. We will continue to share sensitive information with one another. Is this embarrassing? Yes. Is it awkward? Yes. Consequences for U.S. foreign policy? I think fairly modest.”

In testimony at Manning’s hearing on Monday, Patrick Kennedy, the State Department’s under secretary of management, said that in 2011 the department had conducted a draft assessment of the damage Manning caused, but never finalized the report. Kennedy also said a department-wide assessment was never done and that there was no indication there would be because, he said, “the damage continues to roll on.”

The main impact of the leaks, he said, has been a “chilling effect” on foreign officials’ willingness to talk as freely with U.S. diplomats as they had before, according to a transcript of the testimony provided by the Press Freedom Foundation.

When the judge, Col. Denise Lind, asked for more details on how widespread the effect was, Kennedy said there were a “relatively small number of people actually expressing it,” but added that these “feelings” began around 2010 and still persist today.

It is “impossible to know what someone is not sharing with you, and that is, in itself, I believe, a risk to national security,” he added.

The Department of Defense did complete an internal review of how the leaks affected its operations. On Tuesday, Maj. Gen. Michael Nagata, former deputy commander of the Office of Defense Representative to Pakistan, testified that the leaks had affected the mission.

But details are classified — the remainder of his testimony was closed to the public.

U.S. officials are scheduled to continue testifying through the end of the week.

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