We have let it go. We've been letting it go for over 70 years. Strangely, almost all the former empire countries have chosen to remain in friendship in the Commonwealth since leaving the empire - all except one that I can think of off-hand. I'm sure Scotland would join their mates on the outside...
Yeh, we could do that. If Cambridge United can beat Newcastle and all that ..................
Personally, I'm confident that we (with the United States) would win the resulting nuclear WWIII. Trouble is, none of us would ever know if we had or not.