KONSTANTIN VON NOTZ, the leading Green politician on the Bundestag committee investigating American spying in Germany, embodies German ambivalence over America. He asks if the German-American relationship is a “friendship or a mere partnership”. Partnership implies a cynical “mathematics of interests”, so he prefers friendship. But that requires “shared values”, including strict parliamentary supervision over government snooping. That is why he will insist on June 8th, when the Bundestag goes back into session, on seeing what has become known as “the list”.

This list has become a potential timebomb both for Germany’s ruling coalition and for the transatlantic relationship. It refers to the documentation of millions of “selectors”—search terms for phone numbers, e-mail addresses and so on—that America’s National Security Agency (NSA) has over the years fed into the computers of its German equivalent, the BND. The Germans monitored these and passed the intelligence back to America. Under a 2002 deal, the selectors may not point to German citizens, European firms or European Union governments.

But for years the BND failed to check the selectors, according to parliamentary testimony by Gerhard Schindler, its president. It began doing so properly only after revelations of American mass surveillance by Edward Snowden in 2013. The BND then rejected thousands of search terms as impermissible, apparently because they aimed at European firms and governments, including France’s. A big question is just how many problematic selectors had got through. Mr Schindler says he was informed of the situation only in March. How much Chancellor Angela Merkel knew is unclear.

German spies have been left looking like marionettes of the Americans. This is embarrassing for Mrs Merkel. During the 2013 election campaign, after revelations that the Americans had tapped her mobile phone, she said that “spying among friends is just not on.” She gave the impression that Germany would negotiate a mutual no-spy agreement with America. But e-mails leaked to the German press suggest the Americans ruled out such a deal. The opposition parties, and even the centre-left Social Democrats who are Mrs Merkel’s coalition partners, believe Mrs Merkel misled the voters in 2013.

Germany’s allies have notably failed to register outrage. France, an alleged victim of snooping, has not complained. Indeed, after the Charlie Hebdo massacre in January the French are going in the opposite direction, giving more latitude to their secret services. Many in Berlin suspect the French would rather not explain what they have been up to. The British spy as merrily as the Americans, according to Mr Snowden. In 2012 Britain even asked the BND to tap German data pipes and swap information. This operation, code-named “monkeyshoulder”, was stopped by Mr Schindler only in 2013. The Germans seem touchier than others about spying.

America is itself reconsidering the balance between security and freedom. This week it passed the Freedom Act, which gives more privacy protections to the telephone data of Americans—though not of Germans or other foreigners (see page 34). Yet Germans increasingly see America as a bully and threat to their privacy.

Resurgent anti-Americanism is a clear worry. The German Marshall Fund of the United States, a think-tank, has put together a “task force” to improve German-American relations. Among its findings is that German trust in America has dropped, for reasons going far beyond spying—such as Guantánamo Bay, Abu Ghraib or even American capitalism, which many Germans blame for the 2008 financial crisis. A majority (57%) of Germans want to become more independent in their relationship. Such attitudes cloud other business, notably talks on a planned transatlantic trade and investment deal.

Yet some remain sanguine. “Trust runs deeper than expected,” says Annette Heuser of the Washington branch of the Bertelsmann Foundation, a German think-tank. With the Pew Research Centre, Bertelsmann surveyed Germans in late February (before news of the BND’s deals with the NSA) and found that 62% still consider America “a reliable ally”, more than see Britain as one.

The list of selectors could still cause big problems. The Social Democrats, in coalition with Mrs Merkel but running against her in 2017, see a chance to dent the chancellor’s popularity. So, naturally, do the Greens and the Left, in opposition. They want Mr von Notz’s committee to get the list or else take the case to the constitutional court. A different committee, overseeing the BND, also wants the list, and this week threatened to restrict the BND’s mandate if it did not get it.

The Americans want the list to stay secret, fearing it could compromise their intelligence and the security of allies, including Germany. They have restricted co-operation with the BND and could turn off more information taps. As Mr Schindler conceded, “we need them more than they need us.” The search for a compromise is on. To examine the list and report to parliament in secret, a recognised expert might be picked. But by Mrs Merkel or by the Bundestag? Mr von Notz says only the second would be acceptable. That is why the list, not to mention its contents, could prove so explosive.