Twenty years ago, in the aftermath of the federal election, the Germans were stuck. The leftist government of Gerhard Shroeder’s SPD with the Greens had lost the election to Angela Merkel’s CDU/CSU alliance. But not by much; in fact not by enough for a coalition to be created easily.

Indeed, Ms Merkel’s party, together with the liberal FDP, was insufficient for a majority. It seemed the only option was for the SPD to join again with the Greens, but to add the far left PDS, the successor to the Communists who governed the East German dictatorship until 1990. This was too much. The PDS was deemed uncoalitionable; a party too extreme to be an acceptable partner.

Ultimately, the party had to be locked out of government through the formation of the previously unthinkable – a coalition between the two large mainstream parties of Ms Merkel’s CDU/CSU and Mr Shroeder’s SPD. Unthinkably, the GroKo (Große Koalition) was born. It survived a full term and, after a hiatus, re-emerged in 2013 for a further two terms.

Closer to home, in the Irish election of 2020 Sinn Fein upset the apple cart and threw the traditional mainstream parties of Fianna Fáil and the governing Fine Gael into disarray. The left wing nationalists won the popular vote, and in a three-horse race the only way to form a government was for two of the three to come together. The traditional mainstream regarded the rise of Sinn Fein as a matter of concern, and its inclusion in government as unacceptable. The Fine Gael/Fianna Fáil grand coalition was born, survived again in 2022, and again at the end of last year,........

© Herald Scotland