“Supergirl’s” Fortress of Solitude is under threat, but TV’s most popular woman of steel doesn’t mind, especially if the intruder is a young lady with more on her mind than peddling kryptonite-laced cookies.

“Every time a little girl comes on the set and I’m in my suit, their reaction is indescribable,” said Melissa Benoist, the show’s star, during a breather from shooting a scene, just a short jog away from Warner Bros. Studio’s water tower, adorned with a 5,000-pound image of the actress in full costume. “You really see the true effect of what we’re doing here, and I feel a lot of humble pride about that.”

“Supergirl” may or may not be back for a second season — viewership has been shrunk by half since its out-of-this-world premiere in October — but the CBS drama has already fulfilled its mission of bringing some diversity to a TV genre dominated by white men in long underwear.

Other members of this unofficial justice league include Daredevil, the blind crime-fighter who returns with new Netflix adventures this Friday; Luke Cage, an African-American bruiser graduating from “Jessica Jones” to his own series, and Black Canary, who uses her powers of seduction on men and women on the CW’s “Arrow” and “Legends of Tomorrow” (as the White Canary). Kids channel Boomerang is adding “Super Hero High,” featuring female DC protagonists, to its Saturday morning animation block starting next weekend.

Perhaps the most progressive figure on the landscape is Vixen, the creature-channeling heroine raised in Africa. The character has been largely restricted to an animated Web series on the CW’s online streaming service, but a well received appearance on “Arrow” has led to speculation that she will be recruited by “Legends of Tomorrow.”

Vixen may be a groundbreaker in terms of her race and gender, but the series doesn’t dwell on her flight through the glass ceiling.

Same could be said for Jessica Jones, who’s too busy drowning her sorrows in a bottle of blended scotch to read the latest issue of Ms. magazine.

A woman, not a girl

It took a little while for Supergirl to get over her habit of apologizing to men for simply bumping into them on the sidewalk, and she initially chafed at her moniker.

“Shouldn’t she be called Superwoman?” her alter ego Kara unsuccessfully argued to her media-mogul boss, who, in a sweet bit of casting, is played by “Ally McBeal” star Calista Flockhart. “If we call her Supergirl, something less than what she is, aren’t we guilty of being anti-feminist?”

A solid position — but humanity-saving duties quickly eat up any free time she might have to rally around women’s rights causes.

These aren’t necessarily superheroines; they’re just super.

“We never walk into the writers’ room and say, ‘We are now going to take on rape, abuse and feminism,’ ” said “Jones” creator Melissa Rosenberg, whose writing credits include the “Twilight” franchise. “We just want to tell stories for this character [Jessica], and by being true to her, we end up being true to the issues. It all works out.”

The matter-of-fact inclusiveness extends beyond gender. The color of Luke Cage’s skin or Black Canary’s sexual orientation are not ignored, but they haven’t led to “very special” episodes, either.

“ ‘Daredevil’ is the story of a blind man, and yet we don’t land on the challenges of being handicapped,” said Jeph Loeb, executive vice president for Marvel Television. “It’s just part of the ongoing process on who this character is.”

Marvel’s rapid expansion into the TV world is largely due to the $4 billion purchase of the company in 2010 by Disney, which owns ABC. But the partnership also lets the network tap into a wealth of stories and characters that have a better track record in comic books than on television or film.

Black Panther, the first major black superhero, debuted in a Fantastic Four issue back in 1966. He’ll finally make his big-screen debut in “Captain America: Civil War” and is scheduled to get a solo outing in 2018.

The first major gay superhero, Northstar, came out in print decades ago, but was never represented in movies, despite his long-standing connection to the X-Men. He appeared in several episodes of an animated “X-Men” series, but his homosexuality was never mentioned.

“A lot of what we’re talking about now, issues of race and being physically challenged, were being addressed by Marvel back in the ’60s” Loeb said. “This is not a well-kept secret anymore. We’re now getting new platforms in which we can tell these stories in grounded, real ways.”

Super friends of color

In “Supergirl,” Jimmy Olsen is being played by black actor Mehcad Brooks, and in “Daredevil” a character based on comics’ Night Nurse (who’s white) is portrayed by Hispanic actress Rosario Dawson.

There are also advances off camera, although Hollywood still has a long way to go. According to the Center for the Study of Women in Television and Film, only 25 percent of key players behind the scenes of broadcast, cable and Netflix programs during the 2014-15 season were women. A report from the Writers Guild of America last year concluded that one-third of all TV shows don’t employ any minority writers.

The percentages aren’t significantly better in the superhero genre, but that’s starting to change, thanks to women whose doll collections growing up included Barbie and Batman.

“I had Richie Rich in my collection, but I’d sneak into my brother’s room for Superman,” said Sarah Schechter, an executive producer on “Supergirl.” “I loved how you can tell these amazing stories in these short spaces, how you can tell something by showing it rather than talking about it, which we tend to do too often on TV.”

The power of diversity

Greg Berlanti, whose fingerprints are on several DC-generated shows, has made a vow to increase the number of minority and female directors he employs. From the first season of “Arrow” to the second, people of color at the helm of individual episodes have risen in number by 19 to 30 percent. He’s also promised that “Legends of Tomorrow” will feature more diversity on-screen over the next three years.

“The world just isn’t singularly white,” said Berlanti, who has a long-term relationship with L.A. Galaxy soccer player Robbie Rogers and cast openly gay actor Victor Garber in a key role on “Legends.” “I think it’s a real conversation point right now in Hollywood because it should be, and people should be talking about it and doing as much as they can to change the landscape.”

Not all efforts for a more cosmopolitan cast work, though. Netflix just announced that “Game of Thrones” actor Finn Jones will play the title character in its upcoming adaptation of “Iron Fist,” despite a petition circulated by fans for Marvel to consider an Asian-American in the martial arts role.

Diversity is not only the right thing to do; it’s good business. By bringing characters that are relatively unique to TV — a black avenger committed to protecting Harlem, a female Kryptonian who doesn’t dress like she just got off her shift at the strip club — there’s less of a chance that audiences will get tired of a genre that could otherwise overstay its welcome.

“First off, shows have to be great, but they all have to explore something different and be diverse in their own ways,” said Geoff Johns, the chief creative officer at DC Comics. “As long as there’s diversity, I don’t think there is a saturation point.” 

Njustin@startribune.com Twitter: @nealjustin