Just over a year ago, Annegret Kramp-Karrenbauer seemed up-and-coming in German politics. She had succeeded Angela Merkel as boss of their center-right party, the Christian Democratic Union. She even looked like Merkel’s heiress apparent as German chancellor. All that came to a screeching halt on Feb. 10, when Kramp-Karrenbauer said she would resign as party leader, thereby becoming the most notable political victim yet of a far-right party, the Alternative for Germany (AfD).

Modern Germany isn’t Weimar; the AfD isn’t the Nazi party; and German democracy isn’t in danger of failing. Nonetheless, this rupture is historical. It rips wide open the race to become the next German chancellor. It also exposes the helpless failure of the CDU and all of the other centrist parties, at least so far, to find plausible democratic answers to the increasingly devious challenge from the far right.

The origins of this turmoil lie in a region that’s not used to being in the limelight. Thuringia, in what used to be East Germany, has a state parliament that in its makeup resembles legislatures in the Weimar Republic. Two extremist parties, on the far left and the far right, together hold a majority, thus assuring gridlock. By contrast, all the centrist parties that have run national politics since 1949, including the CDU, have in Thuringia been reduced to playing the role either of bystanders or spoilers. Or, as now, idiots, as they walked into a trap the AfD laid for them.

That was possible because both the AfD and the center-right parties, the CDU and the Free Democrats (FDP), had the same stated goal: Prevent a candidate of the Left, the successor of the communist party that used to run East Germany, from being elected state premier of Thuringia. To do that, the AfD nominated a fake candidate (who was later spotted laughing in the gallery). For two rounds of balloting, that candidate denied the Left an absolute majority. But in the third round, when a mere plurality sufficed, the AfD secretly switched its support from its own nominee to a new entrant from the Free Democrats, Thomas Kemmerich.

The CDU and FDP should have smelled the rat. But either they didn’t, or they were fine with it. So both center-right parties voted for Kemmerich, who with the additional support of the AfD came out the winner. Kemmerich should have realized that the victory was tainted and refused to take the oath. But he accepted. Protests broke out across Germany and almost the whole political class disavowed him. Over the weekend, Kemmerich stepped down. He and his family now have body guards protecting them.

Outsiders may wonder what exactly was so scandalous about all this, and what it even had to do with Kramp-Karrenbauer. After all, the duly elected representatives of the Thuringian electorate, in free and secrete voting, chose a premier, just as the state constitution stipulated.

The problem was that the CDU, led by Kramp-Karrenbauer, had given instructions to its local associations throughout Germany to never, ever to co-operate in any form with the AfD, which it considers un-democratic and racist. In the regions that used to be West Germany, most Christian Democrats support this stance, viewing themselves as a bulwark toward the extreme right. But Christian Democrats in the former East Germany are less sure. They tend to see the AfD less as pariahs than as the far end of the mainstream — politically incorrect, maybe, but certainly not “fascist.”

This rift among the conservative Christian Democrats also runs through the FDP, which is usually described as “liberal” in the European, pro-business sense. Rhetorically, both have condemned the AfD since it was founded in 2013, and especially since it entered the national parliament in 2017 and kept drifting right. At the same time, the CDU and FDP both realize that political fragmentation makes it ever harder to form majorities, or prevent them, without factoring in the AfD somehow.

A similar type of  dilemma in fact has accelerated the decline of the center-left Social Democrats (SPD) during the past two decades. What the AfD is for the CDU on the right, the Left, which still fantasizes about Marx and romanticizes the East German dictatorship, has been to the SPD: an extremist rival, but also a tempting ticket to power. In national politics, the SPD and the Left haven’t co-operated yet; in regional government, as in Thuringia, they do so regularly nowadays.

Kramp-Karrenbauer swam into this maelstrom already weakened. For the past year, she’s been sinking in the polls. Even becoming defense minister in Merkel’s cabinet hasn’t helped. Nor has she established her authority within the CDU. When the Thuringian Christian Democrats defied her directions regarding the AfD so openly, she became untenable.

She’ll now keep running the party as a caretaker until it figures out how to choose a successor. Options included Armin Laschet, premier of North Rhine-Westphalia, which is home to the CDU’s largest regional association; Jens Spahn, the ambitious health minister; and Friedrich Merz, a veteran of CDU politics in the 1990s who is considered the most conservative.

But in this race for chancellor, which won’t officially open until 2021, another conservative increasingly looks the strongest: Markus Soeder. He’s premier of Bavaria and leader of the CSU, the CDU’s “sister party.” By tradition, the CDU and CSU, though independent, field one common candidate for chancellor in national politics. And Soeder’s been having a good Thuringian crisis, as it were. When the news broke, he was in front of a microphone at once, ruling out any such “cooperation” between the CSU and the AfD, ever. The big difference was that everybody not only believed him but also believed that he has the power within the CSU to honor that pledge.

It’s too early to make educated guesses about 2021. One thing that’s changed in recent days, however, is what Germans will be talking about. A year ago, the question of how to deal with the AfD was one topic, but not the main one. From now on, it could prove decisive. The AfD isn’t done causing mischief yet. And Germany’s mainstream politicians still haven’t found a good answer.

To contact the author of this story: Andreas Kluth at akluth1@bloomberg.net

To contact the editor responsible for this story: Melissa Pozsgay at mpozsgay@bloomberg.net

This column does not necessarily reflect the opinion of Bloomberg LP and its owners.

Andreas Kluth is a member of Bloomberg’s editorial board. He was previously editor in chief of Handelsblatt Global and a writer for the Economist.

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