Trump believes politics is a staged fight. But it is not. Still, clear words are sometimes needed in politics. In that sense, I believe I am better than Mrs. Merkel.

The stubborn stance of some European governments on the refugee question is a reprisal less aimed at Angela Merkel or (Vice Chancellor) Sigmar Gabriel than at certain people on Wilhelmstrasse in Berlin.

We agree: Brussels can't regulate everything. I'm driven by something else: There are forces in Europe that want to generally give national policy priority over a common European approach. We have to prevent this.

Now Europe are experiencing a wave of eroding solidarity, first of certain societies and then entire governments. At the same time, we have two giant new challenges to meet: the migration movement and terror. And then Great Britain is thinking about leaving the EU. That should suffice as a description.

We need a big debate in society about how we are going to shape Europe and tame capitalism. A government must provide direction and make concrete proposals. It is one of Angela Merkel's biggest failings that she doesn't do this.

Referendums have always posed a threat when it comes to EU policy, because EU policy is complicated. They're an opportunity for those from all political camps who like to oversimplify things.

I would have oriented myself in case of Donald Trump according to what former German Chancellor Gerhard Schröder said to then - U.S. President George W. Bush when the Americans launched a war that was in violation of international law. Schröder showed that a German chancellor can act in a clear and self-confident manner toward a U.S. president.