Europe’s centrists are finally paying the price of their extremism

Friedrich Merz has been German chancellor for less than a year and half, and his approval ratings are at record lows. His centre-right Christian Democratic Union of Germany (CDU), which just lost one state election and was obliterated in another, is in free fall across the country.

The German media cannot talk or write about anything else, blaming Merz for weak campaigning, for boxing himself in...