WASHINGTON, June 14 -- There may be no sharper image of the country's divide than the one set for June 14. On his eightieth birthday, Donald Trump will host a professional cage fight on the South Lawn of the White House, an octagon ringed by thousands of seats with the executive mansion as a backdrop. Across the rest of the country, the movement that calls itself "No Kings" will spend the same day in the streets, staging another nationwide protest against what it describes as a president governing like a monarch. One side is throwing a spectacle at the People's House; the other is marching to remind him whose house it is.

The birthday event is real and lavish. As Fox News reported, Trump has spent nearly a year planning UFC Freedom 250, ...