The motives of a young Afghan man who attacked passengers on a German train with an ax and a knife are being keenly sought. He himself was shot dead by police. The default position, of course, is that he was a terrorist. Daesh (the self-proclaimed IS) may yet claim responsibility for this odious crime, as after 48 hours they did for the slaughter last week in Nice. Now, however, the French are rowing back against the early claims that Mohamed Lahouaiej Bouhlel the man responsible for the carnage on the Promenade des Anglais in Nice was a hardened terrorist. What is clear is that this Tunisian was mentally disturbed. His family near Sousse, scene of last year's horrific beach mass-murder, had sent him to France in the hope that he might become more stable among the Tunisian community in Nice, a great many of whom also come from Sousse. The horrific nature of the German train attack suggests that the 17-year-old Afghan youth could also have been mentally unstable. Considering the disfiguring disasters that have befallen his country, this is perhaps hardly surprising. Now many would argue that to be a member of Daesh and take part in its atrocities is prima facie proof of mental derangement. But in the case of the latest French and German crimes, it is surely right to look beyond the terrorism claims. It is also surely right to consider the reaction of the million-plus refugees, almost all of them Muslim who have been given shelter by Chancellor Angela Merkel's government, at significant political risk to itself. The ax attack will have caused dismay and disgust among the refugees. Muslims know how to respect hospitality every bit as much as they are taught how to give it. Whatever the motive of the Afghan axman, his crime reflects on every other refugee and at two levels. The initial response, of course, is shame that a guest can so dishonor his generous hosts. But then follows disquiet and fear that this senseless attack will reinforce the bigots of the Alternatif für Deutschland party and their exploitation of the fears of ordinary, decent Germans that their country has taken too many refugees. There is a problem here for the no-less-decent Muslim refugees who find themselves in a foreign country to whose ways and culture they are seeking to adapt. German aid officials working with them talk airily of the "refugee community". This is a misrepresentation and they ought to know it. There is no single community. The refugees can be divided not only by country but by region, village, tribe and other networks. For their own practical reasons the Germans speak of the homogeneity of the refugees which simply does not exist. In doing so they have negated the individual community structures that could serve to advise, discipline and direct their members. Thus to the rootlessness that many refugees feel by quitting their devastated countries is added the rootlessness that they discover when they arrive in a strange land. The German authorities are doing what they feel to be best. But they could surely make a greater effort to keep members of different communities together and allow their elders to exercise their judgement and wisdom.