If I am not mistaken, today is a national holiday in the USA to celebrate independence of the 13 original USA states from the UK in 1776. I am sure if they wanted to join the UK they would be welcome!
The UK voted recently to leave the EU. Time will tell whether this was a good move or a bad one. We probably have more in common with the USA than the rest of Europe. Certainly we share a common language.
I like Europe but am not a great fan of the EU as an institution. Like many, in many nations, I am happy with a common market but not a federal Europe. The EU has sadly become an inefficient institution which has not added a lot of value in recent years. Although I voted REMAIN, I am not surprised we voted to LEAVE. It is now up to us to forge our way in the world. In some ways being outside the EU is not so bad.