Countries across the Western world are over-indebted. In theory, they could grow their way out of the debt or rein in their fiscal deficits. But the richer countries have a miserable recent growth record. And as the fall of French Prime Minister François Bayrou this week shows, there’s no public appetite for austerity. The siren of inflation calls. Whether countries succumb depends on how tightly they have lashed themselves to the mast.[....]