By Gideon Rachman
Donald Trump’s travails with his “Muslim ban” make it easy to dismiss the whole idea as an aberration that will swiftly be consigned to history by the judicial system and the court of public opinion. But that would be a misreading. The ban on migrants and refugees from seven mainly Muslim countries was put together clumsily and executed cruelly. But it responded to a hostility to Islam and a craving for security and cultural homogeneity that is finding adherents across the western world — and not just on the far right.