In the long list of problems facing the beleaguered traffic-light coalition, this wasn’t one they’d reckoned with: on Tuesday, for the first time in 28 years, a Greens MP defected to the centre-right CDU.

Melis Sekmen, a 30-year old politician from Mannheim, announced the move in a video and written statement published on her website on Tuesday morning. Describing the decision as “the result of a long process of consideration”, Sekmen said her views on politics had developed over time.

“I have realised that my idea of how and with what style politics is done has evolved,” she said. 

The defection was met with shock and consternation from members of the left-leaning Green party, many of whom responded to the political betrayal in muted tones.

“It’s not a good look,” Cindy Holberg, the vice chair of Baden-Württemberg Greens, told Spiegel.

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“It’s unfair to the voters who wanted Greens and are getting Black,” she added, referring to the flagship colour of the CDU.

But on the other side of the Bundestag, where the right-wing parties sit, the atmosphere was jubilant. 

In a parliamentary meeting with her new CDU colleagues, and those from their sister Christian Social Union Party (CSU), Sekmen was apparently met with applause and a “warm welcome” from CDU/CSU parliamentary leader Friedrich Merz.

“It’s good that you have made this decision,” Merz said. “The parliamentary group is looking forward to getting to know you.”

According to unnamed colleagues of Sekmen’s who have spoken to Spiegel, the former Greens MP had “clapped performatively” at speeches made by the CDU leader in recent debates in the Bundestag. 

Why did Sekmen leave the Greens?

Though there was no explicit mention of political disagreements with her party, Sekmen hinted in her statement that both economic and identity politics had played a role.

Praising her home city of Mannheim in Baden-Württemberg, the former Greens MP said the city had given people “the opportunity to build something for themselves”.

“They have worked hard and thus achieved social advancement,” she wrote. “My family is part of this wonderful story.”

Though little known outside of the Bundestag bubble, Sekmen had specialised in economic politics as a Greens MP, chairing the Greens economics committee and heading up initiatives for businesses and startups. 

Heavily isolated among her left-leaning local party, she had also taken issue with her party’s brand of social politics, such as the reform of long-term unemployment benefits to make the system less punitive.

When her coalition partners, the Free Democrats (FDP), set out an economically liberal 12-point-plan back in April that included slashing benefits and reversing the Bürgergeld reforms, Sekmen said she was open to it.

But perhaps the most thorny issue between Sekmen and the Greens were issues of identity – and especially their stance on Islamism. 

In her statement announcing her defection, she said parties should “name uncomfortable realities” even if they don’t fit in with their political narratives and that those voices should come from “the centre rather than the fringes” of politics. 

“To achieve this, we need a culture of debate that doesn’t pigeonhole people for their opinions or concerns,” she added.

Following the deadly knife attack on a police officer at an anti-Islam rally in Mannheim in May, Sekmen also spoke out in favour of a tougher line on radical Islam and the integration of foreigners.

“It has to be possible to discuss this topic without being pigeonholed,” she told the Frankfurter Allgemeine newspaper. 

That could be one reason that the former Green politician, whose father moved to Germany from Turkey as a child, found a home in the CDU under Merz.

The party’s new programme, which was penned back in May, takes a strong line on foreigners’ integration and a heavily critical stance on radical Islam. 

READ ALSO: Tensions high in Mannheim after knife attack claims life of policeman

What does this mean for the traffic-light coalition?

Though Sekmen is in many ways an Alleingänger – or a unique case – her defection really cuts to the heart of many issues the traffic-light coalition is facing.

The uneasy partnership between the centre-left Social Democrats (SPD), Greens and pro-business FDP has been under increasing strain in recent months, and the fissures are starting to deepen.

This week, the coalition parties are struggling to reconcile their visions for the future in the form of the 2025 budget.

While the liberal FDP wants to slash ministerial budgets, cut benefits and stick to Germany’s strict borrowing rules, the SPD and Greens are desperate to secure funds for their welfare programmes and invest more heavily in infrastructure. 

The endless battles and even existential threats to the traffic-light coalition have taken their toll in recent months, and this latest sign of disagreement within a single party has only added to the sense of chaos.

Originally due to sign off on the law on July 4th, the new deadline is now July 17th, with a draft allegedly due to be presented on Friday ahead of Germany’s match against Spain in the Euro quarter-finals. 

But it’s likely to take more than that for the storm-battered coalition to recover from its dire poll ratings and appalling showings in the recent EU and local elections.

The parties must also find a way to tackle the elephant in the room: the surge in popularity of the far-right AfD and the ongoing culture wars about issues related to identity and integration.

READ ALSO: What do Germany’s far-right gains in EU elections mean for foreigners?

Sekmen’s comments about bringing an Islam-critical stance into the mainstream centre of politics will speak to the CDU, who have been following precisely this strategy in recent months.

The question remains whether that will be enough to reclaim the narrative from the evermore prominent far-right.