Let's say, for a moment, that the revolutions in Nova Scoatia and the siege of Quebec, for various reasons, are successful and British Canada parts way with the metropole during the American Revolutionary War, whether toward independence or as part of the United States.
Then, let's say, Britain is forced to agree to this, at least for the time being. What would the reactions be politically for the United Kingdom if it were to find itself down all its North American colonies, only left with those in the Caribbean as well as Central and South America as a presence in the Western Hemisphere? In particular, what would some of the long-term ramifications be?