For France, it means that a party that is nationalist, xenophobic and Islamophobic may well emerge reinforced – accepted, legitimised and eminently electable to high office in a way that would have been unthinkable even a decade ago. France used to call its barrier to the hard right la digue, or the dam. The floodgates are now open in France, but also beyond. Macron’s successor in 2027 – he is term-limited – may well come from a party whose founder, Jean-Marie Le Pen, called the Holocaust a “detail” of history. Could this resurgence of parties with fascist roots really overturn...