IT's official: Michelle Obama is the first lady of American fashion, appearing on the cover of the March issue of Vogue. Every first lady since Lou Hoover — save Bess Truman — has been featured in the high-fashion magazine, but Mrs. Obama is only the second to grace the cover. She appears wearing a magenta silk sheath dress by Jason Wu, who also designed her inaugural gown. Much of the eight-page feature inside is devoted to Obama's self-described role as “mom in chief” to 10-year-old Malia and 7-year-old Sasha. Being Vogue, though, the conversation eventually turns to clothes. Obama said she is aware of how her wardrobe is being scrutinized, but she makes no apologies for her choices — even the Election Night combination of ripped-from-the-runway, fashion-forward dress and plain-Jane cardigan. “I'm not going to pretend that I don't care about it,” she said. “But I also have to be very practical. In the end, someone will always not like what you wear — people just have different tastes.”