I have seen a lot of similar discussions recently. Let me propose a different answer: none. The ‘importance’ of these countries across the board is unanswerable. Let me give you just two examples 1/3
A) Trade.The US, EU27 and China form the three most powerful entities. The EU has exclusive competences in the area - it is one block. B) military. Here the EU has almost no power, the UK is one of the most important countries - as is also Russia, of far less significance f trade
But even that lacks nuance. Because if you are wondering how to resolve a trade problem in Kazakhstan, you will have to think about Russia, too. The reality is complex.
