She may be the most awful person in Washington, D.C., and there's fierce competition for the title.

Louise Linton, the actress/wife of Treasury Secretary Steven Mnuchin, went full-on Marie Antoinette, essentially telling people who don't dress as fabulously as her that they're pathetic losers.

Linton and Mnuchin were on an Air Force jet Monday, and when they landed they were photographed getting off the plane. She put the pic on Instagram with the caption that read in part, "#rolandmouret pants #tomford sunnies #hermesscarf #valentinorockstudheels #valentino."

Some people went nuts on her -- appropriately -- and some of her retorts are classic and classless ... "Adorable ... I'm pretty sure we paid more taxes toward our day 'trip' than you did. You're adorably out of touch ... Your life looks cute."

She deleted the post, but what a you-know-what.