What caused the need for Brexit, was when Obama destabilized the middle east, resulting in millions of asylum and job seekers storming Europe. This created unplanned stresses in many EU countries, who then found themselves unable to control the fate of their own nations, due to EU rules.
The EU made sense up to the mass migration. It was originally composed of first world countries organizing into a large capitalist cooperative of states. The mass migration of third world population, created huge pockets that averaged second world in first world countries. This gave everyone look at a future that was not in the best interests of the host countries; regress backwards in time.
The main problem with Brexit is too many politicians made deals that benefited themselves and their donors, via the EU charter. They personally, would be sheltered from the chaos of decline. Brexit would take way their deals and their guarantees since it voided the charter. The self serving politicians and donors need to undermine Brexit to get their deals back.
One solution is a modified EU charter that allows individual countries more control during times of emergency and instability. The idea is to go slower in terms of the real long term vision of a first-to-second-to-third world decline toward a socialist empire, run by the political overlords, who sold out each country.
The EU supporters will not allow Brexit a chance, since the people will see this is a better deal for the people, but not for the politicians and donors. The same is happening in the US, where the Democrats and establishment Republicans resist all the Trump changes that makes the old guard look incompetent and self serving.
If all the doom and gloom of Brexit was real, wouldn't the best political strategy be to let it happen so when hey fall on their faces, this never happens again? The real fear is this will work. It has to be undermined with fantasy propaganda of doom and gloom. The left wing of America is running the same smoke screen. My advice is give Brexit a chance, so we can do a reality check. Then a new EU can form that is minus the con artists; new deal that is transparent and does not give politicians any advantages over its citizens.