There's no occasion quite like the Fourth of July to celebrate all things American. Here at Fashionista, we'll be spending the week examining the fashion industry in our own backyard, from the state of U.S. apparel manufacturing to American-born models on the rise. You can follow all of our coverage here.

"They're all wearing casual clothes, yoga pants, T-shirts, jeans," said Tom Ford in a recent interview with WWD, referencing the women he usually encounters during his everyday routine in Los Angeles, whether it's dropping his son Jack off at school, or going out for lunch. "Women aren't wearing day clothes in the way that they used to."

Indeed, the essentials that make up a classic American wardrobe have certainly evolved over time, but the reasons for these choices have remained somewhat constant. According to fashion historian and costume curator Deirdre Clemente, who's covered American style extensively from college students' casual form of dress to the evolution of business casual, America started to find its own aesthetic around the end of World War II; breaking away from Europe allowed Americans to break away from a European-prescribed fashion system as well.

"One of the things that defines American style as opposed to Europe, which has a much more rigid class system, is that Americans have the tendency to dress towards the middle, and this has become progressively true throughout the 20th and into the 21st century," says Clemente. "Starting at about the 1930s, dressing like you have money became uncool."

Clemente's definition of an American wardrobe comes down to practicality and versatility. Workwear clothing, which is often tied to Americana, covers those exact two bases. "Americana style is rooted in heritage workwear — anything from raw denim and utility shirts to field jackets and flannel shirts," says Brian Trunzo, senior menswear editor at WGSN. Think heritage brands like Carhartt, Pendleton, Dickie's and Levi's. Denim jeans, says Clemente, were generally worn by prisoners in the 1930s for their durability, as well as by cowboys and farmers working at rodeos and ranches.

So what defines Americana style today? It's not exactly the heritage brands that sparked the #menswear movement back in the early 2000s, because the manufacturers that built them rarely exist. According to Marketwatch, apparel industries in the U.S. are down more than 80 percent since the 1980s; textile mills have also decreased by about 50 percent since 2000. "Those are the factories and jobs that are really gone for good," reports writer Rex Nutting. And with the current political administration's anti-immigration stance, a comeback for U.S. garment production — currently fueled by skilled immigrants — is quite the challenge.

For women, Americana has always followed a more active lifestyle — casual and functional, says Hazel Clark, a fashion and design studies professor at Parsons. Donna Karan championed this aesthetic with her namesake label, creating her signature collection of separates, or "seven easy pieces" for the woman on the go. With Ford's observation, those seven pieces would likely be different today — and involve a pair of leggings, too. NPD Group has coined it "spashion," a hybrid of the booming athleisure and activewear markets mixed with fashionable attire that has consumed nearly every American’s closet. The runways in Paris during Men's Fashion Week — and Couture Week, too — also proved sportswear's universal impact, thanks in part to the meteoric rise of streetwear.

"It's pretty interesting how the icons of American style — jeans, T-shirts, hoodies — are often riffed upon by people outside of America, and that somehow reenergizes that garment," says Matt Sebra, Digital Style Director at GQ. "Champion hoodies are everywhere right now, but would Champion hoodies be everywhere without Vetements? Probably not." Sebra likens it to the raw denim resurgence 10 years ago from Japan. "On a global stage, people look to America for these practical, wearable garments, but then can riff on them. Therefore, it becomes something new, and people want to buy again and again," he says.

Trunzo sees this cross-pollination of sub-genres and influences as well. "It's totally appropriate for streetwear tropes to affect things as pure and untouched as Americana. That being said, it works both ways. Everyone is influencing each other. Thanks in large part to the biggest scapegoat in history: the internet," he says. "Yes, I do think Americana is still rooted in workwear — will always be rooted in workwear — however, it's being influenced more and more by many other things."

The early instances of this could be normcore's successor: gorpcore, a result of outdoor brands like Patagonia, North Face and Columbia finding their places in more sartorial-savvy wardrobes. "I think that would be the link between traditional Americana and the new age of tech performance wear," says Trunzo. "Who's to say it's awkward to wear a colorblocked Patagonia-esque pullover with a traditional piece of workwear — let's say a utility jacket — with tights from a performance brand and a pair of streetwear shorts over it? That sounds so ridiculous when you say it, but when you think of it, that just sums up the runway looks we've seen in Paris."

So is streetwear the new Americana? Is it "spashion"? Or have we already moved onto gorpcore? To be quite honest, Americana style is hard to pin down. "There is a lot of interesting variations because this country is not monocultural or monotonic," says Clark. "That's what has been fascinating about this country in the last 100 years. It has been truly multicultural, multiethnic and multiracial and that is also embedded in different takes in Americana." Plus, with immigrants running America's biggest fashion brands — Raf Simons at Calvin Klein, Stuart Vevers at Coach, Jonathan Saunders at DVF, as well as Laura Kim and Fernando Garcia running Oscar de la Renta — different takes on defining American style will only continue, and that’s a good thing.

"America is a melting pot and continues to be a melting pot," says Sebra. "What's really interesting about American style today is that it really reflects that and increasingly in the people producing it, the designers, as well as the output of clothes. There's no singular defining element to them. It's all based in practical and wearable things but the scope is much more global than it has ever been."

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