Politically, it means that whenever cooperation is exposed between the C.I.A. and the BND, the public reacts furiously — for example, when it emerged during the Iraq war that the German government had given the Americans coordinates for targets around Baghdad. The media pressed the defense minister for an answer; sweat poured from his brow as he tried to explain why this did not constitute participation in the war.

The C.I.A. staff in Germany was certainly watching, and they clearly concluded that the Germans might not be willing participants in their spy games. From their point of view, sharing intelligence with the Germans must be like being on a pub crawl with a member of a temperance society.

I asked Joseph T. Wippl, who was the C.I.A.’s Berlin station chief in the early 2000s, why the agency had recruited German sources. “The C.I.A. has developed strongly in the direction of a third world agency, in that its officers work in places where the U.S. has great leverage over others and where there is no rule of law,” he said. “They are not used to or have not been trained to work in countries with similar democratic, constitutional institutions.” At the same time, he went on, the Germans had never seemed interested in the level of cooperation that might obviate this sort of unilateral snooping — the sort of treaty relationship that America has with Australia, Britain, Canada and New Zealand, the so-called Five Eyes intelligence alliance.

To suggest that the Germans could be treated as a Sixth Eye is a flattering idea. Yet I doubt the Germans would accept the honor. As is the case with America’s nuclear umbrella, we’re happy to have the protection while being still happier not to have to carry the responsibility. If Germany entered into a real intelligence alliance with America, the government would have to deal with a load of dirty knowledge — and lose the benefit of plausible deniability.

Does all this justify the level of mistrust C.I.A. spies show Germany? No. We might be law abiders, but we’re neither naïve nor America’s enemy. As far as anyone knows, this country has never withheld crucial information from America. Remember the alleged mobile anthrax factories that Secretary of State Colin L. Powell presented at the United Nations as a case in point for invading Iraq? The informant behind this claim — code name Curveball — was a BND source.

The C.I.A. needs to stop wasting time, energy and money on our intelligence people — and respect us Germans as we are. A bit reluctant at times, but generally highly reliable. As in any relationship, respect will be worth a lot more in the long run than the short-term gains of impatient snooping.

Jochen Bittner is a political editor for the weekly newspaper Die Zeit.