The old battle between Christian Democrats and Social Democrats is now meaningless, not least because the social structures that underlay those parties, the church and the unions, have faded away. Nationalists and populists understood this change earlier; now the rest of the political world needs to understand that the political lines have been redrawn and it's time to change.

We may be reaching the end of the liberal world order.

I don't want to predict calamity. But I am afraid of a new Russian occupation of parts of Eastern Europe. Also of a new Russian campaign to exert influence in Germany or other parts Europe, aimed at making continental politics less democratic. I am afraid of a US trade war and even a shooting war with China.

The surge in right-wing populism and the phenomenon of Trump are related. You can think of them together as the same problem.

We can't continue assuming that politics is something which is decided elsewhere by distant leaders in a distant capital. Protest is insufficient too. If people who are willing to put time into demonstrations also prove willing to work on behalf of candidates in local elections - or to become candidates themselves - they will achieve far more. If all of this upheaval provokes more involvement, then we have a slim chance of ending up with more vibrant democracies eventually. The alternative, as you've hinted, is that democracy fails altogether.

The Soviet Union was, by the 1970s and 1980s, relatively stable and predictable. Putin's Russia is much more volatile. Nuclear policy is really in the hands of one person, or a small group of people, instead of a huge party-state apparatus. The possibility of a mistake is greater now.

Americans have long felt that NATO isn't doing its job and that the Europeans aren't contributing enough. Trump has accelerated the decline in Atlantic solidarity by offering open contempt for NATO allies as well. The future of NATO now very much depends on Europeans. Can you begin to identify security threats, prepare yourselves and arm yourselves without the US?