Indeed. Look at the Mongolian empire - once the greatest empire in the world, yet now is completely irrelevant and a dusty nowhere.
Just because we are British doesn't mean we won't risk a similar collapse in the very long term.
But it's not just us, it's the whole of Europe really. I've spent the last couple of weeks travelling the Gulf states and it's clear where the money and power is going. Europe as a continent is rapidly becoming just a pretty tourist backwater.
The Gulf states will only be prosperous as long as there is a substantial demand for oil.
With the move to electric cars, and the increasing concern about climate change, there may no longer such a demand in 50 years time.
As regards the UK, I can remember growing up in the 1970s, and we were really up **** creek then.
Never mind inflation at 10%, what about 25%, and the government having to ask the IMF for a bail out.
The changes bought about by Margaret Thatcher were painful for some, but I do think some kind of some kind of economic change would have happened whatever the result of the 1979 election, or if there had been a different leader of the Conservative party at the time.
I also remember a lot of hope that "...things would only get better..." when Tony Blair was elected in 1997. I am not sure that the Blair government delivered on all the promises that they made when they were first elected, and I bet Saint Tony was glad to get out in 2007 before the brown stuff hit the fan with the financial crisis hit in 2008.
I have even heard it said that some in the Labour party were glad that they lost the election in 2010, because it meant that the nasty old Tories would have to take all the difficult decisions regarding recovering the economy after the financial crisis. Remember the treasury minister who wrote the "...there is no money left..." note, and thought it was a joke.
As for the future, whoever wins the next election will have as their number one priority recovering the economy from the effects of COVID, and sorting out the housing market and the NHS. I don't think there will be any substantial change to our relationship with the E.U. during the lifetime of the next parliament.