Nationalists in the UK have not liked what President Obama had to say about "Brexit" at the BBC. And he is not the only prestigious American who believes that the Out vote is a very bad idea. Nationalists in other European lands should pay attention too. The most important and prestigious democratic leader in the world (among other great personalities) is against European frangmentation:
The UK could take up to 10 years to negotiate trade deals with the US if it leaves the EU, Barack Obama has said.