Bobby Chesney on Opinio Juris argues that this is not a good week as far as cooperation between Europe and the US on counterterrorism is concerned. He cites as example of bad cooperation, the decision of an Italian judge based in Milan who denied Seldon Lady, a CIA Agent in Italy, diplomatic protection.
The problem is all in the interpretation of cooperation. One thing is to have an agreement on how to proceed on counterterrorism; another, totally different, thing is to allow US agents to use force and behave illegally on a foreign territory without taking notice of this fact.
The judge in Milan had good evidence of the breach of Italian law committed by the CIA agents. The only possible argument against that decision is to show that the evidence was not sufficient. But to claim that cooperation is not working is just misleading.