The Social Democrats (SPD) tried and failed to defeat Angela Merkel in four elections over 12 years. On three of those occasions, they ended up joining her in a governing coalition. Now they may be finally on the verge of driving the German chancellor from office.

The bad news for the SPD: This scenario would further divide an already riven party and lead to another electoral disaster. Significant factions within the SPD are calling on the party leadership to quit the coalition with Merkel's Christian Democrats (CDU) and their Bavarian sister party, the Christian Social Union (CSU).

They're angry over a deal allowing the outgoing head of Germany's domestic intelligence service, Hans-Georg Maassen, to move to a slightly higher post as an interior ministry undersecretary.  The SPD wanted him removed from office for alleged sympathies with the far right.

SPD chairwoman Andrea Nahles agreed to the deal on Tuesday evening with Merkel and Interior Minister Horst Seehofer.

But lower down the hierarchy and in the grass roots, Social Democrats cried foul. Nahles was accused of being "outmaneuvered" by CSU leader Seehofer and selling out party ideals by accepting the "dismissal via promotion" arrangement. Dissenters are venting their dissatisfaction with their own party's leadership and broaching the possibility of the SPD leaving the government, if conservatives do not yield on the issue.

"There's one outrageous bit of news after another — enough is enough," tweeted SPD interior affairs expert Lars Castellucci, articulating a frustration felt by many Social Democrats.

A breakdown of the coalition due to a civil war in the SPD would be a massive blow, if not an utter catastrophe for Merkel. The veteran chancellor is regarded internationally as a source of stability in a volatile world.

"Every day in this coalition is a lost one"

The opposition to the Maassen compromise and, implicitly, to Nahles' leadership is being led by the party's youth wing, the Jusos. Their charismatic leader Kevin Kühnert, who played a role in the demise of former SPD leader Martin Schulz earlier this year, has tweeted statements ranging from "Seehofer has shown us all the middle finger" and "every day in this coalition is a lost one." And he's demanding that the SPD's senior committees be given the right to cancel the deal Nahles negotiated.

To paraphrase the movie "Network": the party youth is mad as hell and don't want to take it any more.

Read more: German press review: Maassen promotion a win for the right

"They are so disappointed right now," fellow Juso Annika Klose told DW. "They thought the one thing social democracy is strong for at the moment is the fight against the far right. They're disappointed and don't know what to do."

This particular discord has history. Early this year, Kühnert and the Jusos campaigned against the proposed coalition with Merkel.  and the conservatives. Party members eventually voted in favor, but the rift was only bandaged, not healed. It has now fully re-emerged around the Maassen deal.

"At some point you have to pull the emergency brake," said Flensburg mayor Simone Lange, a coalition critic who ran against Nahles for the post of party leader this spring.

The largely unknown Lange received one-third of SPD delegates' votes — an embarrassment for the party's new chairwoman and a sign of a fundamental, underlying dissatisfaction with the SPD's cooperation with Merkel. 

Party preservation or reinvention

Ironically, the fate of the coalition and Merkel's ability to govern rests with the embattled Nahles. She was forced to send a letter to party members and go on German TV on Wednesday to argue that the Maassen deal was a bitter pill worth swallowing in the interest of social reforms and global stability.

"Mr. Maassen isn't worth paralyzing the government and holding fresh elections for," Nahles said, while acknowledging that the coalition was in "rough waters" at the moment.

Would the Social Democrats, who have dipped below 20 percent in almost all national public opinion polls, really risk triggering fresh elections just to emancipate themselves from Merkel?

The general secretary of Merkel's CDU seemed to think so on Wednesday evening, when she informed party members per email about the Maassen deal: "There was a concrete danger that the government would break apart, with all the consequences that would entail, including fresh elections."

High-level sources say that the SPD members of Merkel's cabinet, who will need approve Maassen's transfer, remain firmly behind both Nahles and the coalition.

So with good reason, conservatives feel that they can still rely on the SPD's instincts for political self-preservation.

"We don't need to worry," a veteran conservative leader with former connections to the interior minister told DW. "If there's a party with reason to fear new elections, it's the SPD. But we should worry about something else after the events of recent days: that more and more people are shaking their heads in disbelief and turning their backs on politics."

But alienation is a powerful force, and it's not just the general public that feel turned off by the Maassen deal.

Kühnert and the Jusos have repeatedly expressed their comfort with the idea of fresh national elections. They're willing to accept the likelihood that the SPD might do worse than the abysmal 20.5 percent of the vote it got in the 2017 national election in return for the chance to go into opposition and reinvent the party. And many think that if such a scenario ends Merkel's political reign as well, then all the better.

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