20% of Five Eyes is in Europe. That's one good reason.
edit: Why the downvotes? As an EU citizen, I'm directly affected by this, and I very much do not like the idea of the EU towing the Five Eyes line to further fascilitate US foreign policy interests.
We very much would like to make our own decisions in our own interests and not have all our policies decided and forced upon us by the biggest brother on the planet.
In that context, I doubt the EU is gonna let itself get dictated what to do by the UK, which is in the process of leaving said EU. It would be like eating your cake and still having it.
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