The choice of Paris as the venue for a summit of the European “coalition of the willing” to discuss a “reassurance force” for Ukraine this week has turned out to be deeply unfortunate; for five days after the summit, France may well not have a government. Then again, it’s not clear that any other European capital would have made for a better choice. France has been plunged into a renewed political crisis by the decision of the prime minister, Francois Bayrou, to hold a parliamentary...