The alliance that for decades was called the "firewall" of German politics cracked last night in a way no statement can paper over. According to exit polls, the Alternative for Germany took 44.5 percent in the state election in Saxony-Anhalt. Almost half of all the votes in a federal state, for a party that has never yet run one.

Chancellor Friedrich Merz's Christian Democratic Union, the party that kept Germany as a byword for stability, fell to around 23 percent. Half as much. That is not a lost election, that is erased ground.

The party that has never governed - now on the threshold

The AfD had been leading the polls for months on over 40 percent, and its candidate for state premier Ulrich Siegmund openly demanded at least 45. So nobody was surprised. And that is the more interesting part of the story: everyone knew what was coming and nobody had anything to offer against it.

Until now the AfD has not led a single German federal state. An absolute majority would let it bypass what Germans call the Brandmauer - the informal rule that established parties do not cooperate with it. A rule that works exactly as long as the arithmetic allows.

And this time the arithmetic is tight. Forty-four and a half percent of the vote does not automatically mean a majority of seats - that depends on how many smaller parties clear the five percent threshold. If the AfD falls short of an absolute majority, forming a government becomes far more complicated, because the other large parties have ruled out a coalition with it in advance.

The test that was not about Saxony-Anhalt

The vote in this east German state is not a local matter. It is the first real assessment of the Merz government's policies, and the assessment is harsh. The AfD built its result on four themes: migration, security, economic discontent and contempt for the existing political establishment. Not one of them is invented - they are all real problems that somebody else should have answered first.

The AfD's state organisation in Saxony-Anhalt is classified as a far-right extremist organisation by the state office for the protection of the constitution. The party rejects that classification. So, evidently, do 44.5 percent of voters.

If the projection holds, this is one of the AfD's biggest political breakthroughs since its founding, and a serious signal ahead of elections in the other eastern states. The Balkans have heard the lesson many times over that labelling an electorate does not shrink it - it grows it. The question is whether Berlin is listening now.