German parties are often referred to by their colors, where red stands for left-leaning, green for environmentalists, and black for conservatives. So could a "red-red-green" coalition come to pass at the federal level? Angela Merkel, who is not running for reelection, has warned against this: "With me as chancellor, there could never be a coalition involving the Left," she stated in parliament in early September. "And whether this is shared by Olaf Scholz or not, that remains open."

The Social Democrats' candidate, Olaf Scholz, who currently serves as finance minister and vice-chancellor, named conditions for any coalition, including a commitment to the North Atlantic defense alliance (NATO).

The Left party wants to abolish NATO, put an end to all Bundeswehr missions abroad, and ban all weapons exports. Their election program states: "We call for the dissolution of NATO and its replacement by a collective security system with Russia's participation."

However, Germany's withdrawal from NATO is an absolute no-go for the SPD and the Greens. For both parties, the transatlantic partnership is a pillar of their foreign policy.

So a red-red-green alliance is only conceivable if the Left Party were to give in on this point. But there are no signs of that. In an interview with DW, the party's co-chair and top candidate for the election, Janine Wissler, reiterated her rejection of NATO: "After the disaster we are currently experiencing in Afghanistan, I think there is one party that now has relatively little reason to reconsider its foreign policy positions. And that is the Left Party."

Although the Left Party categorically rules out foreign deployments of the Bundeswehr, humanitarian "blue helmet" missions under the leadership of the United Nations (UN) might be a compromise.

There has also been some movement in the discussion about armed drones. These weapons, the use of which the Left party has flat-out rejected, are also controversial within the SPD. At their party conference in June, however, the Greens voted by a narrow majority in favor of using them to protect German soldiers if necessary.

Climate change, education, immigration

The overlap between the three parties on foreign and security policy is small. But in many other important areas, it should be easier for them to come together. Whether combatting climate change, education, finance, or health — programmatically they are relatively close. All are in favor of a complete switch to renewable energies, better digital infrastructure in administration, schools, and businesses, and higher minimum wages. A red-red-green coalition is also unlikely to fail over higher taxes, especially for the wealthy, which the Left Party and the SPD advocate for.

Things could get more difficult when it comes to migration and asylum policy. Although all three parties do not intend to curb immigration, the SPD candidate for chancellor has spoken out in favor of continuing deportations also to Afghanistan in certain cases. Olaf Scholz left no doubt about this in the DW interview: "It is right that someone who commits serious crimes cannot count on being able to stay here. And that is also part of the protection of refugees."

Coalition alternatives

In purely mathematical terms, more alliances than ever seem possible. In theory, the SPD and the Greens are the most flexible. They could potentially team up with any party except for the far-right Alternative for Germany (AfD) — and indeed have already done so on the state level.

The pro-free market Free Democrats (FDP) and the CDU/CSU, on the other hand, reject coalitions with the left as a matter of principle. If the conservatives want Armin Laschet to become chancellor in the post-Merkel era, their only hope at the moment is to head a coalition with the FDP and the Green Party. This was already on the horizon after the 2017 federal election but failed after weeks of talks due to the surprising withdrawal of the FDP under leader Christian Lindner.

Longtime observers of German politics such as Oskar Niedermayer believe that a red-red-green coalition is possible. The differences in foreign and security policy ideas are the "biggest stumbling block," he said. But people from all three parties are already working on "finding lines of compromise," the political scientist told DW back in May.

Another 'red socks' campaign?

The CDU's latest warnings against a left-wing coalition bring back memories of the "red socks campaign" in 1994. "Red sock" is a term that is mostly used in a derogatory way for a person on the political left. It was famously used by the center-right in their general election campaign back then to warn against a possible coalition of the SPD with the Greens and the predecessor to the Left party, the PDS. The CDU printed large-format campaign posters showing a clothesline with a red sock dangling from a green clip. "To the future, but not in red socks," it read.

The CDU's coalition partner at the time, the FDP, bought into the narrative: "Those who don't want socialists and communists to again have a say, must choose the middle-class by voting for a strong FDP," said then-party chairman and later Foreign Minister Guido Westerwelle.

The strategy may have paid off: This allusion to a communist threat and the emotions of the Cold War was seen as one of the decisive factors for the narrow election victory of Helmut Kohl's black-yellow coalition government that year.

Critics lashed out at the CDU's campaign, calling it an all-too-obvious attempt to discredit left-wingers. But the PDS took up the campaign aggressively and reinterpreted it as advertising for itself, printing red socks on a number of promotional items.

The SPD has always tread lightly on the issue of cooperation with the Left party. Now, as the conservatives are digging the trenches along the same old lines, SPD candidate Olaf Scholz has taken care not to commit to any alliance — but to not rule anything out either.

This article has been translated from German and was updated since publication to reflect the latest developments.

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