BERLIN — A week after CDU party leader Annegret Kramp-Karrenbauer's shock announcement that she will be stepping down, Norbert Röttgen – the first candidate who has put himself forward to replace her – has laid out his plans for the party if he were elected.

Röttgen belongs to the ranks of men who during Merkel's time in power have found themselves pushed to the back benches after an embarrassing blunder – in his case, a humiliating local election defeat in North Rhine-Westphalia. He stuck it out though, which shows courage — and yet raises questions.

For 20 years now, it has been women – most prominently Angela Merkel – who have been at the helm of the CDU. But now that there's a leadership contest to choose her successor, no women are joining the race. Promising candidates such as the party's deputy leader Julia Klöckner and Susanne Eisenmann, Culture Minister for the state of Baden-Württemberg, have not put themselves forward. That's a shame, and it sends the wrong signal to women in the CDU. If they won't put themselves in the mix, they shouldn't be surprised when male colleagues set the tone of the debate, vaunting their own capabilities with perhaps a little too much self-confidence.

There are structural reasons why women are not putting themselves forward.

To avoid any misunderstandings: of course it doesn't say anywhere in the CDU's constitution that only women can be party leader. Of course, after two decades of female leadership, there can be a male successor. But there can equally be a female one. This isn't a question of whether a man or a woman takes on the leadership, but of how the CDU can preserve its reputation as a party that appeals to men and women, old and young, from all walks of life. That will not be possible if it doesn't attract female voters.

The CDU chairmanship remains vacant after AKK's resignation: Kay Nietfeld/DPA via ZUMA Press

There are structural reasons why women are not putting themselves forward, but the causes also lie in the party's internal relations. The late hours involved in politics put many women off, as does the fact that they are still often judged on physical appearance. And the CDU has still not achieved equality within the party. The fact that there has been one female Chancellor has distracted from the reality that the party still has a long way to go in terms of gender equality.

Merkel was groundbreaking in many ways: as a Protestant, an East German and a physicist with a PhD. But now that her Chancellorship is coming to an end and her anointed female successor has thrown in the towel, it is clear that the CDU is lacking in female leaders. It has no female state Minister Presidents, only one woman among its regional party leaders, and hardly any female mayors or municipal council leaders. Only one fifth of the party's representatives in parliament are women. This cannot be allowed to continue if the CDU is to be a party that genuinely represents society.

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