In all of my speeches I talk about why a strong Europe is necessary in order for Germany to be strong over the long term. I think that I have sufficiently shown over the past years that I have a clear notion of how we can make Europe stronger, more democratic and more inclusive. There is really no competition there with Sigmar Gabriel.

For German Social Democracy, Europe is vital to the national interest.

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.

We're at a historical juncture: A growing number of people are declaring what has been achieved over the past decades in Europe to be wrong. They want to return to the nation-state. Sometimes there is even a blood and soil rhetoric that for me is starkly reminiscent of the interwar years of the past century, whose demons we are still all too familiar with.

We are in the middle of a tough, ideological conflict that is being waged across the entire continent. On the one side are those who say that global challenges like migration and terror cannot be met with national parochialism. On the other side are those who would like to see a renaissance of the nation-state.

If we want to defeat Islamic State, we first have to arrive at a cease-fire agreement in Syria. Once that has been achieved, an anti-IS coalition can be assembled, including Russia, Saudi Arabia and Iran. That, however, will be significantly more difficult in the wake of Turkey's downing of the Russian plane.

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.