There is a very strong reason why the UK should leave the EU.
Germany started both the first and second world wars, because they wished to take over Europe and to dominate the world. The UK, together with the Commonwealth armies stood alone, for parts of both world wars and were supported by USA in the second half of the 2nd world war. On both occasions the Germans were defeated.
World War One was one of the deadliest conflicts in the history of the human race, in which over 16 million people died. The total number of both civilian and military casualties is estimated at around 37 million people.
The Second World War was also devastating, it caused the death of three per cent of the world’s population. In Europe alone, 39 million people died, half of whom were civilians.
The Holocaust, also referred to as the Shoah, was genocide during World War II in which Nazi Germany, aided by its collaborators, systematically murdered some six million European Jews, around two-thirds of the Jewish population of Europe, between 1941 and 1945.
Even after being defeated in the 2nd world war Germany still wished to dominate Europe. They joined with France and Italy, who had fought with Germany for parts of the 2nd world war, and other countries firstly to form the Iron, Coal and Steel Community and laterEuropean Economic Community (the EEC treaty), signed in Rome on 25 March 1957.
They did not invite the UK to join them until 1973. By this time the structure of the EU had been formed and that structure is the reason why the growth rate in the EU has been slower than that of the other G20 countries.
As a result, the UK has never had the say in EU affairs that it would have had. If it have been invited to join the Iron Coal and Steel community in 1951 it is possible that the UK could have saved the EU from some of its disastrous decisions.
Although it was not disclosed, at the time of the formation of the Iron Coal and Steel community, Germany and France made plans that they would create the United States of Europe by stealth steps in the following treaties :-
The Treaty of Rome, The Treaty of Maastricht and the Treaty of Lisbon.
Germany and France still plan to create the United States of Europe by 2025.
However, that is now unlikely, for reasons which are covered in other articles on this website. But it still could happen.