Have you never heard of the Prisoner's Dilemma? Even if nobody wants the status quo and everyone would like to cooperate, all we can see is other actors strongly incented to betray each other.
And if you see how nothing in Germany could be decided that affects the UK, what do you think would happen if German and French banks had refused to fund bailouts for the less responsible EU companies? No effects felt outside of Germany?
I am aware of the prisoner's dilemma but it does not apply because it assumes no communication between the prisoners. And even though it is just some gut feeling, I believe most game theoretic problems and paradoxes are irrelevant in real world situations because they arise from artificial constraints and countries wanting to cooperate can just try to remove such constraints if they exists.
And I did not say that the decisions in Germany (or any other country) can not influence the situation of other countries, I said they can not influence them to a degree that justifies espionage. So how does you example apply? Germany and France are free to support or not support what ever they want. How would having known such decisions before they were publicly announced made any difference?
And if you see how nothing in Germany could be decided that affects the UK, what do you think would happen if German and French banks had refused to fund bailouts for the less responsible EU companies? No effects felt outside of Germany?