I can't just go up to people standing in the snow at the German-Austrian border and ask them: "Are you an Islamist?" When people flee to us from war zones, we first have to help. But we also have to be quick to look very closely at who it is that is coming.

People aren't stupid. They saw what was happening at the Cologne central station. A lawless space was created in the middle of a city of over a million. That has to be addressed and it has to be done so in a sober-minded way.

We also can't be naïve when it comes to the refugees. Men who commit violence should of course be deported to their countries of origin. We already have enough problems here and we don't need to import anymore.

We need to finally be proactive in enlightening people from Islamic cultural groups. And this applies to immigrants already here as well as to current refugees. The German constitution stands above the Sharia. Schools need to offer classes on gender equality. You also have to offer an alternative to young men with a penchant for violence.

Of course we in Europe also have epidemic, structural sexual violence. Violence is always the dark core of dominance. The men who are now coming to us from Islamic cultural circles are, of course, shaped by conditions there, which are still much more antiquated than here. That's a problem that we have ignored for far too long. In the name of a false tolerance, we have accepted that women are kept at home like prisoners and are forcibly married.

But if we keep denying that there are problems with some male immigrants, then we will just drive the people into the arms of the right-wing populists. Without the ignorance or the trivialization on the part of all the political parties, there would be no Pegida or Alternative for Germany.

Mastery of the German language and the acceptance of our legal system has to become part of the criteria for naturalization.