Grant Wood’s American Gothic is among the most acerbic of the paintings at the America After the Fall exhibition (at the Royal Academy until June 4). The Wall Street Crash was making fools of those who believed in the American Dream, while the farmers of the Midwest were being driven into the dust by falling crop prices. Wood chose the flattest medium he could muster – elongated, with bas-relief paintwork, with a modernist hint on the flat landscape – full of pathos and loaded with irony at the mess these founding fathers had left America in. In recent times, American Gothic has become popular again, with original and bootlegged versions gracing covers of several British magazines.