We have a single currency, many laws are exactly the same and come from Brussels and there is movement towards closer political union, but still police officers in Europe have a problem sharing information. It does sound incredible but it is the sad truth. There is now a dispute between European police officers over who knew what about the attackers in Barcelona. It appears that sensitive information was not passed from one force to the other. The Spanish prime minister, Mariano Rajoy, is now calling for closer co-operation, but I sincerely doubt that it will solve the problem.

I always get the impression that security services in different countries are reluctant to share information for fear that it might compromise a source and might fall into the wrong hands. But at a time when Europe is facing a massive terrorist threat, international security agencies need to work as one. Perhaps the European Union could consider setting up a counter-terrorist department which could channel all the necessary information to the various security services.

Mistakes will always happen but something needs to be done and fast to ensure that there is a flow of information, especially with Europe's open borders. While Britain may be leaving the European Union, it still needs to play a key role in the fight against terrorism with its European partners.