Invested: The triumph of Trumponomics

Dr Arthur Laffer is the guru of US tax policy. Earlier this year, before either party had selected its candidates, Laffer’s base in Nashville, Tennessee, was a shrine for the nearly dozen Republican party pilgrims seeking benediction for their economic policies.

Among them was Donald Trump, who was then regarded as highly unlikely to get the nomination among a field that included Republican royalty such as Jeb Bush and seasoned party operators like ...