For the most part, presidential inaugurations are moments of communal pageantry. There is music and poetry. There are oaths to recite and vows to make. Everyone smiles for the cameras, and everyone dresses up — for the inauguration on the steps of the U.S. Capitol, and later for a series of balls that have come to symbolize the great promise of a new administration.

Where does the first lady fit into all of this? She has never said much amid the ceremony and ritual. But in ideal circumstances, she helps humanize the president while adopting a persona as American royalty. She is, for better or worse, the hostess of what is often presented as a modern fairy tale.

Perhaps that was why so many people had a visceral reaction when Rosalynn Carter recycled a dress she already worn when her husband, Jimmy Carter, was inaugurated as president in 1977. The Carters had been hoping to channel the idea that they felt the economic pain of regular people, an old pledge from the campaign trail. But nobody wanted them to be regular people, not during the inauguration and not when they were dancing at their galas.

Tastes, of course, have evolved. (Hello, sequins. Goodbye, fur.) And first ladies make personal choices. But in the end, it is largely about a carefully constructed image and conveying messages about priorities — something that has often been done through fashion.

Vanessa Friedman contributed reporting.

Produced by Christy Harmon