Edmund Stoiber, chairman of the Christian Social Union in Germany, threw the country’s mostly completed coalition negotiations into disarray last week by announcing he would not join the cabinet of Angela Merkel, the Christian Democrat chancellor-to-be. In so doing, he gave the world a refresher course on the enduring opacity of German democratic politics. If Mr Stoiber really wanted to remain minister-president of Bavaria, as he now says, why did he quit that job and prevail on Ms Merkel to make him a super-minister for economics, a job he now says he does not want? That is only one of the ambiguities. Why did Mr Stoiber, an ardent partisan, claim to have based his decision on the Social Democrats’ choice of cabinet members? Even Mr Stoiber’s party colleagues could not explain his thought process.

Part of what makes German politics so hard to read is the absence of an element present in virtually all western democracies: a body of publicly debated, right-of-centre doctrine. Whether that means the right-liberal politics of Baroness Thatcher and Ronald Reagan, or the hybrid ideology of George W. Bush, Germany does not have it. It is easy to point to Mr Stoiber’s mix of Catholic social values and corporatism but harder to say whether his departure shifts Ms Merkel’s government “right” or “left”, or alters nothing. German politicians do not talk that way. So Mr Stoiber’s departure looks personal, and arbitrary.