(CNN) First lady Melania Trump exited Air Force One Sunday in Tokyo, Japan, dressed smartly in a coat by Italian fashion house, Fendi, a leather pencil skirt by her frequent couturier, Hervé Pierre, and her ubiquitous sky-high Manolo Blahnik heels.

The first lady, accompanying her husband President Donald Trump on his first official trip to Asia, will again have her turn in the spotlight, due in part to a familiar phrase: "What is she wearing?" That "she" being the first lady of the United States, be her Laura Bush, Michelle Obama, and now, Melania Trump.

Like it or not, how the first lady presents herself sartorially can oftentimes be a headline grabbing part of the job. And for Trump, fashion has emerged as a key messaging tool.

"Mrs. Trump always wants to be thoughtful and respect the traditions and protocols of the countries she visits," her communications director Stephanie Grisham told CNN. "She knows she is representing the United States, and wants to be sure she is appropriate in all that she does."

Trump's last lengthy journey overseas in May, again accompanying the President, took her to Saudi Arabia, Israel, Belgium and Italy, and the talk was mostly about what she wore. From the black Stella McCartney jumpsuit with that bold, gold Yves Saint Laurent snakeskin belt to the demure black lace Dolce & Gabbana coat dress for her audience with the Pope, and that $51,500 floral jacket for an outing in Sicily, again by Dolce & Gabbana, Trump's choices made news.

"Mrs. Trump is someone who knows the world of high fashion quite well and appears to care a great deal. Her choices are considered, and therefore I find it entirely appropriate to read between the lines, or the seams, as it were," says Elizabeth Holmes, a style reporter who for several years helmed the fashion beat for The Wall Street Journal. "I think it is important that people in high-profile roles are thoughtful in their style, and I appreciate when they use those choices to say something more."

"Michelle Obama used her personal style to amplify her policy agenda and connect with average Americans," she added. "Mrs. Trump dresses beautifully and, for the most part, appropriately for the occasion -- save for a few questionable stiletto moments. It is still relatively early in her time as first lady, but I hope Mrs. Trump begins to do more with her clothing."

Regional choices

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At her first stop, in Hawaii on Friday, Trump wore a white, sleeveless dress with a thin, dark belt, and while the look was simple and unembellished, it was in fact a custom silk Christian Dior, the ivory sheen matching well with the white floral lei she was given to wear around her neck upon arrival.

Departing Honolulu Saturday, she picked a dress with a tropical motif by relative unknown label Borgo De Nor, available on a handful of internet shopping sites for $1,090. Yet while appropriate, Dior, Borgo De Nor, and, today, Fendi, are neither American nor Japanese labels, another indicator that Trump, as she has done before, isn't necessarily nodding to the fashion diplomacy guidelines that most first ladies have taken pains to adhere to.

"First ladies typically use fashion to support famous American designers, to put the spotlight on emerging designers, and, on trips abroad, to pay tribute to foreign designers," said Kate Andersen Brower, a CNN contributor and author of "First Women: The Grace and Power of America's Modern First Ladies."

"Because their role is so undefined, it's one of the only constants we see throughout modern history. At a dinner with French President Charles de Gaulle, Jackie Kennedy wore French designer Givenchy; during 1970s inflation, Rosalynn Carter wore the same gown to her husband's presidential inauguration as she had when he became governor," Brower said. "Michelle Obama was brilliant at this -- she wore an Indian-American designer to the India state dinner, all British designers on a trip to London, and Kenzo in Tokyo."

In Germany in July, Trump did represent an American label, Michael Kors -- the white fringed dress she wore seated next to Russian President Vladimir Putin for an official G20 dinner was a showstopper, to say the least. And, again in July, this time in France for Bastille Day celebrations, she wore another Dior, a red skirt suit cut to resemble the silhouette of the iconic French designer's very first collection.

Ready for every occasion

Grisham told CNN that for this trip, Trump is ready for every occasion.

"She is planning her wardrobe around each stop and visit, which I believe is pretty typical of anyone who is packing for a trip," she said.

Holmes hopes those looks include the opportunity to finagle a bit of love for designers, in the name of diplomacy.

"I appreciate when someone as high-profile as the first lady uses her platform to call attention to a designer in the country she is visiting -- with extra credit for pointing the spotlight on new or emerging talent" she said. "Mrs. Obama did so beautifully -- my favorites were the state dinner moments when she wore Tadashi Shoji for Japan, and Naeem Khan for India. Kate Middleton has done it, too. Typically these well-documented official trips offer several well-photographed style moments."

And while some of Trump's fashion choices back home have drawn critical fire -- the dress she was wearing in a photo tweeted by the President in support of American-made products on Labor Day was by Mary Katrantzou, a Greek-born designer based in London, or the $1,390 red flannel shirt by French designer Balmain, worn to a garden event with children at the White House come to mind -- this is not a first lady who appears to care all that much what people have to say about what's in her closet.

In September, asked how Trump dealt with the opinions of her detractors, Grisham told CNN: "Mrs. Trump will never fit into a mold and is not concerned about the comparisons often made of her. The first lady wishes to make a difference in our country and hopes that regardless of political affiliation, everyone will realize she is her own individual."

Earlier this week, Trump did get words of support from one of the few women to have walked in her shoes, former first lady Laura Bush.

"I think she's done a lovely job. She's a beautiful woman. She's a wonderful representative for the United States," Bush said in an interview with CNN, adding that she wished the first family the very best.