‘Is that a Banksy on the wall or have we had a visit from Peter Mandelson?’

Judging by how well it fares in the annual UN World Happiness Report, there’s not much rotten in the state of Denmark. It regularly tops the UN chart and while it might feel slightly glib to compare wealthy nations with warzones – why can’t those gloomy Afghans, languishing at 147th, cheer up? – the wider