The only way the Euro would be "forced" on the UK is if we leave and then re-apply to join at a later date, at which point it will become a term of joining just like any other applicant. So if this is a concern, it's better off to stay with our current membership terms which are not on any kind of tram lines towards the Euro. If it did happen, I wouldn't have a problem if it was of economic benefit to the UK and considered financially safe by economists. On a practical level it's just a currency after all, money is money. Our membership fees were £9.4 billion net in 2017, which amounts to about £143 a head. Not exactly "exorbitant" given the benefits we get in return. I'm guessing you already feel this is too much, but at what point does it truly become "exorbitant"? I would say when the costs outweigh the benefits by a significant margin. But currently the benefits outweigh the costs by a very significant margin. European Army is an emotive term. What are we talking about here? Peace keeping force? A replacement for NATO? An aggressive force to counter threats from Russia etc? Voluntary? Conscription? You'd have to define what you mean here before you could expect a reasoned response.