Call it punk-rock efficiency.But Jon Langford is quick to deflate any lofty notions that may linger in connection with that hoary old rock ‘n’ roll chestnut, the “concept album.”More than one reviewer has pinned that description on Deserted, the Mekons most recent release. For many, the term still conjures up visions of rock stars working through their mommy issues (Pink Floyd’s The Wall) or bloated rock-opera tales of deaf, dumb and blind kids (The Who’s Tommy), so it’s hardly surprising that the self-described “old pirate punk rocker” doesn’t want to lend it too much weight. Deserted is not based around a set narrative, but it does contain over-arching imagery and themes that reflect its creation.“I think it would be really hard to make an album without a concept and if you did it would be fairly boring,” says Langford, in an interview from a tour stop in Philadelphia. “All our albums are concept albums. That’s not pretentious, we actually think about what we want the album to be. So yeah, there’s a concept. This one was one of a series of site-specific recordings that we’ve done, where we’ve actually gone to specific places to get together, write material, record it simultaneously and take on board details and stories and atmospheres of the places we’ve been.”For 2015’s Jura, for instance, a slimmed-down version of the band (dubbed the Mini-Mekons) descended on the remote Scottish Island of the same name with American singer-songwriter Robbie Fulks to write and record a batch of stripped-down acoustic numbers and sea shanties. On the followup, 2017’s Existentialism, the band gathered at a theatre in Brooklyn for songs that were both recorded in front of and made use of a live audience.This time around, the British-American veterans ventured to California’s Yucca Valley in the Mojave Desert, not far from Joshua Tree National Park. The area possesses its own hazy place in the rock and roll mythos, with everyone from U2 to Gram Parsons, Jim Morrison and Victoria Williams decamping there at one point or another to soak up its ethereal beauty.For the eight-piece collective, who were enjoying a boost in profile and string of sold-out shows thanks in part to the well-received 2014 documentary Revenge of the Mekons, it was the perfect time and place to “ponder the vastness and weirdness of the desert.”“Nobody told the Joshua trees where the park ends,” says Langford, one of the the Mekons four lead singers. “So we were in the compound up the other side of the hill and there was Joshua trees everywhere and all the trappings of desert life. It was fantastic and beautiful. There were big cool evenings with campfires and skies full of stars. It was only a brief stop, I think were there four or five nights, but it was fairly compelling and a great place to initiate a project and bash down loads of things and see what we had later.”“No one was really sure what we had,” Langford adds. “When we came to mix it in L.A., it was clear that, unconsciously at least, we’d put something quite coherent together.”For longtime fans of the Mekons, there is plenty of the band’s beloved hallmarks to soak up on Deserted. Musically, it celebrates the band’s ability to lash together country, folk, punk, dub and Celtic music into something completely its own. When it comes to lyrics, the band employs a similarly dizzying collage of allusions, political commentary and clever wordplay, giving shout-outs to everyone from actor Peter O’Toole to French poet Arthur Rimbaud to shirtless proto-punker Iggy Pop.Underneath the fray are thematic threads that seem particularly timely for political progressives such as Langford, who has long made the U.S. his adopted home.“There’s all sorts of deserts creeping over, expanding,” says Langford, who will be playing with the Mekons on Saturday, July 27 as part of the Calgary Folk Music Festival. “So there is that and there’s notions of surviving in very harsh conditions. It feels to me that people with leftist, progressive views are probably feeling a bit like that at the moment. How do you survive this onslaught? Things you’ve worked for and things you’ve taken for granted have come under attack.”“So you arm yourself with thorns and bury yourself in the ground and then emerge again when it rains,” he adds with a chuckle.The Mekons have possessed a literary, leftist bent ever since they came charging out of the University of Leeds Fine Arts department in the mid-1970s, which was a fertile time and place that also produced post-punk legends such as Gang of Four and Delta 5. Since 1985, when the band recorded its pioneering cowpunk classic Fear and Whisky, the Mekons lineup has remained fairly stable, although Langford and others have engaged in a wide variety of side and solo projects over the years.Langford’s own history with the Calgary Folk Music Festival dates back nearly 20 years, when he first played Prince’s Island Park as a solo artist. He has returned at least four times since then; once more as a solo act, twice with the Mekons and once leading his side project, the Waco Brothers. For the festival’s 40th anniversary this weekend, Langford will be pulling double-duty with both the Mekons and Jon Langford’s Four Lost Souls.Having been around long enough to live through, and comment on, other dark periods for political progressives in the band’s 40-year-plus history — Ronald Reagan’s reign in the U.S. or Margaret Thatcher’s in the U.K.,for instance — Langford acknowledges that living through divisive times is nothing new. In fact, he sees the Donald Trump presidency as a symptom of what Reagan and Thatcher created.“He is the inevitable consequence of this short-sightedness and greed that they fostered,” he says.What about the silver-lining concept that, in the very least, times like these make for interesting art?“Yeah, if we’ve got time,” Langford says. “I worry because I’ve got kids. I’d sacrifice the art. Their life is going to be … I don’t know what will happen in America. There looks like there will be some sort of civil disturbance and violence that will not be what we want it to be. To be honest, I’m really worried about it.”The Mekons play National Stage 4 July 27 at 7:40 p.m. and Jon Langford’s Four Lost Souls play July 28 at 3:15 p.m., also on National Stage 4 as part of the Calgary Folk Music Festival on Prince’s Island Park.