Given recent German indignation about the National Security Agency, it has been easy to overlook the fact that for decades the German government has cooperated extensively with the NSA on surveillance activities. But after a high-level meeting in Berlin this week, this long-standing but veiled cooperation may have a firmer legal and political base.

The two countries’ past partnership became so extensive that they even developed a special logo for their joint signals-intelligence activity, known by its initials, “JSA.” It shows an American bald eagle against the colors of the German flag, next to the words Der Zeitgeist, or “the spirit of the age.”

Like so much else we know about the NSA, the details about its activities in Germany come from Edward Snowden, the former NSA contractor now living in Moscow. He provided a trove of secret documents to Der Spiegel, which published more than 50 online last month.

German anger about U.S. spying boiled over recently with the expulsion of the CIA station chief in Berlin. The Germans were furious when they discovered that the CIA was paying a “walk-in” German agent, adding to their anger that the NSA had tapped Chancellor Angela Merkel’s cellphone.

In an attempt to heal this feud, White House chief of staff Denis McDonough met Tuesday in Berlin with his German counterpart, Peter Altmaier. A senior German official told me his government was “very satisfied” with the meeting, especially McDonough’s proposal to develop “guiding principles” for cooperation on intelligence matters. While not a formal “no-spy” pledge, this agreement might reassure Germans that their rights would be respected.

The NSA’s relationship with Germany dates back to a 1962 pact with the Bundesnachrichtendienst , or BND, as Germany calls its federal intelligence service. According to a Jan. 17, 2013, NSA document summarizing the relationship: “In the past year, Germany displayed both eagerness and self-sufficiency in transforming its SIGINT activities and assumed greater risk in support of U.S. intelligence needs and efforts to improve information sharing within the German government, with coalition partners, and NSA.”

Perhaps most striking, given German public rage at U.S. snooping, the NSA summary credited its German partner for helping to reduce privacy obstacles: “The BND has been working to influence the German government to relax interpretation of the privacy laws over the long term to provide greater opportunity for intelligence sharing.”

The senior German government official affirmed that the intelligence partnership has been “very extensive” and said “we are very happy with this cooperation.” He didn’t dispute U.S. estimates that the NSA has helped disrupt more than 50 terrorist plots, including more than 20 in Europe. But the official cautioned that to gain German support for continued partnership, the United States must be more open about its intelligence activities, and avoid actions that violate the rights of German citizens.

“The problem we face in Germany is not about intelligence collection anymore, but about public sentiment. The public is extremely upset, and the German government has to take this into account,” the official said. Pressed about why the German government hadn’t been more honest with its public about the extent of past cooperation, the official said “it’s a very bad moment to say it’s ‘all right,’ ” after the Snowden revelations.

Germany had felt “the ball was in America’s court,” post-Snowden, and was waiting for the United States to set a new framework, the official said. Tuesday’s meeting seems to have sent the message that Merkel wanted to hear.

Merkel and other German supporters of continued cooperation will have a political battle ahead. When Der Spiegel published the Snowden documents, an accompanying story summed up why many Germans were upset: “No other country in Europe plays host to a secret NSA surveillance architecture comparable to the one in Germany.”

The Der Spiegel documents describe the extensive collaboration. “In addition to the day-to-day collection, the Germans have offered NSA unique accesses in high interest target areas,” noted the January 2013 summary. Another document explained that during a January 2012 meeting, a senior German official “sought NSA’s assistance with intercepting Skype transmissions.” A third document describing a planned BND visit in May 2013, slightly more than a month before Snowden’s leaks began appearing in the press, noted that top BND officials “continue to express a desire to increase CND [Computer Network Defense] engagement with the NSA.”

Cooperation between the two countries’ spy services “is deeper than previously believed,” as Der Spiegel put it. The United States and Germany are now attempting to rebuild the partnership so that it is more transparent and, perhaps, develops a more solid political base.

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