THE NEW YORKER magazine covers are often topical, of course, but for the two most recent issues, they have particularly tapped the power of polarization.

On Monday, the front of a new issue was graced by “First Thanksgiving,” a Bruce McCall painting that struck a cultural two-fer by spoofing Thanksgiving and satirizing the Redskins naming controversy — deriving pointed humor from the tension between its colonial-era Native Americans and its white, name-appropriating “hosts” in modern Washington jerseys.

On newsstands this coming Monday is a cover that’s starker still. Anticipating the grand jury’s no-indictment decision for Officer Darren Wilson in the Ferguson, Mo., slaying of Michael Brown, artist Bob Staake rendered “Broken Arch” — an illustration in which Eero Saarinen’s iconic St. Louis structure has a gap at its apex, with its now-divided, sky-reaching ribs symbolically tinted black and white. (Each of the two backdrops is also chromatically segregated, heightening the overall effect.)

“I lived in St. Louis for 17 years, moving there from Los Angeles,” the Massachusetts-based Staake tells The Post’s Comic Riffs. “As an outsider, I think it gives me a unique and uncommon look at the city’s deep-rooted dynamics. …

“It is a beautiful city, but it didn’t take me long for me to perceive its ‘ugly’ racial underbelly — which is not uncommon in many other major American cities,” the illustrator continues. “As an artist/journalist who experienced the city’s dynamics firsthand, I used that knowledge as a filter for all the news coverage of Ferguson that I read, heard and saw.”

Comic Riffs caught up with Staake (a decades-long Post contributor and Style Invitational artist) to talk about his creative process, his cultural influences — and how conceptual artists commonly arrive at very similar ideas when mining the same Zeitgeist with the same symbolic tools.

MICHAEL CAVNA: Congratulations on the powerful cover, Bob. You’re no stranger to viral attention for your cover work, but what’s the reaction to this one been like? And has any aspect of that reaction surprised you?

BOB STAAKE: I’m always humbled when any of my New Yorker covers stimulates significant viral attention. When that happens, it reaffirms in my mind that I’m doing what I should be doing as an artist: creating images that spark discussion, debate and reflection.

When a cover of mine doesn’t engender a certain Zeitgeist, I wonder if I have somehow failed as an artist. The thing is, my best New Yorker covers provide a visual embarking point, offer graphic clues, but absolutely rely on a smart, educated reader to flesh out the image and interpret it in their own way. It is only by their personal decoding of the art that it suddenly makes a statement that speaks to them — uniquely and individually.

CAVNA: I’m curious: Because Ferguson is such a blanket-coverage story, it’s so easy to follow it in so many formats — from deep magazine essays and newspaper op-eds to roaming CNN live-shots and Twitter hashtags. How have you yourself followed this story over recent days, if not long months?

STAAKE: I lived in St.Louis for 17 years, moving there from Los Angeles. As an outsider, I think it gives me a unique and uncommon look at the city’s deep-rooted dynamics, even as St. Louis didn’t really welcome an outsider like me with open arms. It is a beautiful city, but it didn’t take me long for me to perceive its “ugly” racial underbelly — which is not uncommon in many other major American cities. So as an artist/journalist who experienced the city’s dynamics firsthand, I used that knowledge as a filter for all the news coverage of Ferguson that I read, heard and saw.

CAVNA: So was this cover one of those “thunderbolt” ideas, striking you out of the blue, or was this the result of a more methodical process — perhaps a ticking-off of relevant symbols? What’s your creative process — and was this concept a typical process for you?

STAAKE: I love the idea of a “thunderbolt.” My best New Yorker covers are ideas that strike me like a BANG, and seem to come out of nowhere. This most current cover, “Broken Arch,” actually came about three weeks ago when I was watching a CNN news report about the rumors that there would be no grand-jury indictment. Immediately in my mind, I saw the continuous and connected Gateway Arch — but divided among racial lines. I tried to explain the idea to my wife, she couldn’t quite “see” it, so I went to my studio to draw it up. When she saw the completed design, the idea suddenly made complete sense to her — no words were needed, no yammering — just a simple and [hopefully] poetic image that spoke in a quiet way through the language of art.

CAVNA: This cover feels of a piece with your famed Rainbow Columns at White House cover (“Spectrum of Light”) for the New Yorker in 2012, upon Obama’s endorsement of gay marriage. That is, symbolic colors on an iconic structure to reflect a hot-button cultural moment in America — although tonally, in emotion and color, they are so different. And both covers resonated with so many. Could you speak to any particular similarities or differences that strike you about the two — or in relation to any other of your covers?

STAAKE: As an artist, I have never wanted to live in a vacuum — and that isn’t always easy when you work in solitude in your studio. I leave my house, I walk those 60 steps, I stoke the fireplace, I turn on NPR and the BBC, I read The Post and the Times, and I try to find a way to condense and distill a big issue into a succinct graphic statement. My brilliant art director at The New Yorker, Françoise Mouly, and I have often talked about how different a classic Norman Rockwell Saturday Evening Post cover is from a New Yorker. “With Rockwell,” she’ll say, “the entire story is in the art — but with a great New Yorker cover, we expect you as a reader to ‘figure it out’ and make it sing.” I could not agree more. To the extent that my covers rely on color, allusion, metaphor and parodies of accepted referential points, I always use whatever tools necessary for me to drive my point home in the most concise and streamlined way.

CAVNA: When you create a cover like this one, what are some of your aims — what do you most focus on? Is it to have a conceptual “take” on the story, or are you trying to channel your emotional response to it? [I know as a longtime editorial cartoonist, I often tried to do both.] Do you have a heat-seeking mission?

STAAKE: How can I through art find a way to get down to the bare bones, here? How can I reduce this insanely complex issue into a single image? My job is to find a way. More important, I absolutely want to create a graphically evocative image that forces the reader to react. I’m not averse to creating pretty pictures, but to produce a piece of art that causes a reader to think, that ultimately pushes an otherwise flat image into a completely new dimension.

CAVNA: Did Françoise [Mouly] have any feedback on your sketch or sketches — was this idea revised at all in discussion prior to publication? Or was it: “Run as is!”?

STAAKE: This was a cover that I created independently. There was no sketch, just my final color artwork. While editorial input can be helpful, the cover was created, submitted, and then I hoped for the best. At the approval stage, every single one of my New Yorker covers then become an editorial conversation between David Remnick, Françoise Mouly and myself — and I wouldn’t have it any other way. This particular cover, however, was not changed, altered or modified in any way, and that is pretty rare for a New Yorker cover.

CAVNA: Speaking of your responding to this story, you have roots in Los Angeles, and perhaps might remember, though you were quite young, the Watts Riots — which were also sparked like a match-head by a black suspect/white officer incident at a car, and began nearly 50 years ago, almost to the day, as when Michael Brown was killed. In the Ferguson story, do you see echoes of the Watts Riots or the Rodney King-verdict reaction, to cite L.A. events?

STAAKE: While I was a very young boy in Los Angeles and remember the Watts Riots, I am certain that the Rodney King incident/verdict subliminally helped to inform my “Broken Arch” cover. The secret manner in which the grand jury in St Louis conducted itself, this gave me –and many others in Ferguson and across the nation — great pause. Again, having lived in the city for 17 years, I unfortunately had no doubt whatsoever that the grand jury would not indict. Failing to put all the cards on the table and allow witnesses to be cross-examined — I think that simply fed into the city’s racial divide and lack of trust in the process itself.

CAVNA: So, to pivot toward the hands-on artmaking: You’re noted for being a fan of older digital-art programs, like PhotoShop 3.0. What did you use to create this cover — and do you sketch on paper first, or is every step digital?

STAAKE: I am fortunate to have a weird mind that can sort of handle the whole “sketching” process in my brain, so for this particular cover, there wasn’t a pencil sketch. So much of the image relies on stark colors to make its points, so by skipping the sketch phase and going straight to final art, I got an immediate sense that the design would “work.” The other nice thing about submitting the final art in lieu of a sketch is that Françoise and David then know exactly how the cover will look. Many times, my sketches simply evoke my broad ideas and aren’t a good indicator of how I would complete the art if and when the rough sketch was approved.

CAVNA: Editorial cartoonist R.J. Matson noted that he did a “divided Arch” cartoon, but I would contend that because illustrators work so often in the language of symbols, most every iconic structure or site in the United States — from the Statue of Liberty to Mount Rushmore to the Space Needle — has been used in cartoons and other illustrated commentary. Could you speak to this “Yahtzee” effect a bit? Readers might be surprised by it, but most zeitgeist-surfing cartoonists I know rarely are.

STAAKE: R.J., me and every other editorial cartoonist and illustrator accepts that when we rely on using established, iconic architecture to make our points, similar graphic ideas and concepts are bound to be published. When five editorial cartoonists in five different cities essentially create the same cartoon showing the Statue of Liberty shedding a tear after the collapse of the World Trade Towers, we call it the “Yahtzee effect” — but I call it the “two-artists-walk-into-a-cocktail-party-and-realize-they’re-both-wearing-the-same-dress-effect.”

When my cover came out [online], within moments The New Yorker received an email with R.J.’s previously published editorial cartoon showing the arch crumbling and divided at the top, the south leg labeled ‘WHITE,” the north leg labeled “BLACK.” That was the first I saw the cartoon. No conspiracy here, folks — talk to any cartoonist or conceptual illustrator and they will assure you that this happens all the time.

CAVNA: What’s on your drawing board/screen right now — and do you have any projects you’re particularly excited about?

STAAKE: Four children’s books for Random House, Abrams and HarperCollins, character designs for a major animation project, more New Yorker covers — oh, and I also have to finish building a second wall of bookshelves in my studio.