Four attacks that killed 10 Germans and injured dozens in the space of a week demonstrate that Germany is no safer than other European countries from the scourges of political terror and random outbursts of extreme violence. Given that two of the attacks involved recent migrants who appear to have been inspired by Isis, the militant Islamist group, the demand for a firm reaction from the German authorities is understandable. Yet Germany has a special responsibility to strike a prudent balance between the imperatives of law and order, civil liberties and international legal obligations to refugees in a manner that will set an example for Europe as a whole.

Germany opened its doors last year to more than 1m refugees, largely from conflict-ravaged Afghanistan, Iraq and Syria. The German government’s generous initiative drew criticism from some European allies, and the latest attacks will make it no easier to forge a common European response to the refugee crisis. But the “welcome policy” also aroused increasing concern in sections of German society, stoked tensions in the centre-right political bloc led by Chancellor Angela Merkel and contributed to rising support for Alternative for Germany, a rightwing populist party defined by its strident anti-Islamic, anti-immigrant attitudes.

The task that faces Ms Merkel and her coalition government is to allay the anxieties of many citizens that the welcome extended to the refugees risks becoming a colossal blunder that will destabilise German society. The sexual assaults and robberies in Cologne and other cities on New Year’s Eve were early signs that this task will not be simple. Moreover, German security officials are alert to the danger that Isis might have smuggled operatives into the country under cover of the refugees, and that jihadi networks are identifying migrant youths for recruitment.