Germany has really been pushing against the United States after the NSA revelations from whistleblower and NSA analyst Edward Snowden. The country has pissed the Americans off by sending a helicopter to look for listening posts at the US consulate in Frankfurt, Germany.
The helicopter flew over the consulate twice, hovering just 60m above the building itself, where German staff took high resolution photos of potential surveillance equipment on the roof. They didn't find any listening posts on its August 28 flight, but Spiegel magazine definitely had something to say: "The message to the American friends was meant to be: 'Stop. Germany strikes back!"
Personally, I don't know what the German's were thinking - it's the NSA, they wouldn't just have an iPhone on top of the US consulate listening in on conversations. They'd have terminals within the consulate hacked, or microphones underneath or behind items within the consulate itself.