Suppose if Flanders and Wallonia would join our ranks again. Flanders would be able to cope well: it is wealthy, the infrastructure is reasonable but would need some major adjustment over the coming years but it is Wallonia that we should be worried about;
Other people may think that Wallonia looks like this:
Unfortunately: that is not the whole story... there is more to it:
Particularly the area around Lidje (Luik) and Tchålerwè (Charleroi) has a problem. Particularly the area known as Borinage has a problem. It was once "Belgian's" version of the Black Country. Very heavily industrialised this is where the money was - unfortunately when the mines closed so did the industry (that was during the 1960s and nothing has happened ever since). But... all the more reason to look into the area and see what can be done. - it would indeed need a lot of structuurplannen. While the Flemish only see corruption and decay and only have their ancient hatreds for the Walloons we of the North are maybe a bit more neutral here and we can see chances.
The area around Lidje has been industrialised since the Middle Ages - it is an area where indeed Dutch industrial history was written. Think of Cockerill. With the technological know-how that is now focussed in and around Lidje we could bring the steelworks back to life and build trains there, cars, watches, if necessary weapons. All this produced by people who can be brought back from their slumbers and get paid a Dutch wage, a good wage and can be proud of themselves again. But first we would need a lenghtly inquiry into the causes of political trouble there.
The Borinage is a different story: the question is-- what can be done for these people ? The mines are closed -- that story is over (like in Limburg).
But first things first: these people need decent houses with modern facilities:
It may be the same boring crap as we have but at least it will work.
They are going to need new public transport, new motorways.. new everything (basically)... an expensive job but a worthy one.