Ms. Merkel's attempt to present herself as a Social Democrat was a clever move. But it's not working anymore. The divisions between the CDU and CSU have simply become too great for that.

If we want to create new rules of globalization, then we can't just think in terms of the nation state. The nation state has long offered protection. But it suffers from the fact that many citizens increasingly fear that it can no longer protect them: The threat of transnational terrorism is growing. Freedom of movement rules in Europe facilitate social dumping. Regardless of the make-up of the next government, it must have clear ideas on how to overcome the lack of direction of recent years.

At the end of the day, men like Donald Trump need to be given that which they themselves dispense: clear messages. I would confront him as clearly and explicitly as possible. It is not only the right, but also the duty, of the leader of a German government to do that.

When it comes to climate protection, the whole world will have to pay the price. But if Donald Trump intends to conclude a trade agreement with the EU, he will have to abide by our climate standards. In any case, waiving climate protection does not make American products more competitive.

Ms. Merkel's attempt to present herself as a Social Democrat was a clever move. But it's not working anymore. The divisions between the CDU and CSU have simply become too great for that.

I have friends in politics who really put the friendship to the test through their behavior.

There are certain reactions that you aren't allowed to show in Berlin, for example that you feel offended. If you do, the best-case scenario is a sympathetic article along the lines of: Nice guy, but he's not up to it. The alternative is to don a suit of armor and become cynical. But that's not healthy either: Cynicism is the worst characteristic a politician can have. That's why you have to have an internal balance in Berlin, so you can stay true to yourself. And I have that.