So the British will get another vote (it voted in favor of staying in the EU in 1975) on membership in the EU.
In terms of long-range geopolitics, I think the voters of the UK have two eventual fates to choose from :
- it can remain part of a 500+ million people economic and political grouping and use its position to limit the ability of the Germans and French to try and dominate the EU, and have the combined economic and geopolitical resources of Europe balance the geopolitical and economic power of the other major global powers
Or it can become a 60+ million people "little Britain" (and likely "little England" since the Scots prob would move for independence if England votes to leave) trying to carve a position of influence in the world in face of the economic and geopolitical powers of a 320+ million USA, 1.2+ Billion China and India, over 100+ million Russia, the growing power of the new giants such as Brazil, Nigeria, Turkey and Indonesia, and a continental Europe of close to 500+ million dominated by the Germans (with French assistance).
At best, without the Empire to fall back on as in 1940, a Britain outside the EU would have to hope and pray that the USA continues its support of Britain as a "junior partner" in the greater Anglophone world (kind of as it was during the Iraq war, with Blair playing backup to GW Bush). Otherwise, I fear Britain will find its path to continued political and economic influence in the world overwhelmed by larger powers.
I hate to say it, but a "Little Britain" is not really the optimal solution to securing Britain's position in the 21st century world. As much as the European Union project does result in a loss of some local control over various social, economic and geopolitical policies, it also provides Britain with a platform to help continue to shape the EUs evolution, reduces the dominance of Germany and France over the EU project, and provides the geopolitical and economic resources to successfully compete in a world of much larger economic and geopolitical actors.
In my opinion, Britain inside a 500+ million EU will be much more secure, economically and geopolitically, than a "Little Britain"/"Little England" either as the USA's "junior partner" or, potentially, all alone in the world.
Let the debate begin .....