“Market Angst as U.K. Edges to Exit,” proclaims the headline on the Wall Street Journal’s lead story. The exit referred to is Britain’s departure from the European Union, a move that will be mandated if a majority votes Leave rather than Remain in the national referendum next Thursday.

This outcome would be as astounding, to use the word Lincoln chose in his Second Inaugural to describe the Civil War, to British and European financial markets and political insiders as Donald Trump’s victory for the Republican nomination has been to their American counterparts.