Lying prone on a rug adorned with the Great Seal of the United States, the woman who might someday be first lady is wearing high-heeled sandals and a crimson bikini.

The date is February 2000. Donald J. Trump hasn’t yet thrown his hat into the ring as a Reform Party candidate, yet he’s already set in motion a machine that 15 years on will turn a voluble political maverick into the front-runner for the Republican Party presidential nomination.

The woman on the rug is Melania Knauss, a Slovene model, who at 29 is almost a quarter-century younger than her billionaire future husband. The rug is a prop in an Oval Office set mocked up in a Manhattan photo studio. Spread across two pages of the now defunct Talk magazine, Mr. Trump is seen in an inset close up; telescope back from the picture and what you’d see is Mr. Trump seated behind the presidential desk and at his feet his future wife, a woman striking in her beauty and docility.

If it is always the case in politics that you “play a role,” as Ms. Knauss observed in a caption accompanying those photos, you do this because politics is, above all else, “a business.”