It is more accurate to call it panic than plotting. This week I spent time in the company of members of Angela Merkel’s Christian Democrat party. Startlingly for an outsider, the conversations turned on whether the German chancellor would survive the refugee crisis. Some thought she had just weeks to turn things around. Never mind that only yesterday she had towered above any other European leader. Overnight, the unthinkable has become the plausible — for some in her party, the probable.

Other voices say the fever will subside, but Ms Merkel’s vulnerability speaks to the convulsions across Europe caused by the tide of refugees from Syria, Iraq, Afghanistan and the Maghreb and Sahel countries of Africa. In the eastern, post-communist part of the continent, the influx has strengthened the hands of the ethnic nationalists who never quite signed up to the idea of liberal democracy. To the west it has bolstered the fortunes of nativists such as Marine Le Pen’s National Front in France. Rallies of the far-right Pegida party in Germany now feature speakers who lament the loss of concentration camps. If Britain’s David Cameron loses his referendum to keep Britain in the EU it will be because emotions over migration trump economic self-interest.

Ms Merkel has rarely been called a conviction politician. Her longevity in office has resided in her skill in finding the natural point of balance in the German national mood; and, it should be said, her ruthlessness in despatching potential rivals. The adjectives most often applied to her leadership style, sometimes with more than a note of frustration, have been cautious, deliberative and consensual.