Maybe I've missed something but why would Britain and EuroSyn care about the Atlantic at all? It's not like WW2/Cold War where vital convoys from the US and Canada have to cross over, if the entire Atlantic ends up swarming with Soviets subs then.... good? There is nothing there that Eurosyn care about. Trade is going to be across the Channel, in/around the Med and maybe to bits of Africa, but even then I have doubts.