There are a number of unusual sights in the Columbus Circle bookstore opened last week by Amazon.com, the online mega-retailer that has upended the publishing industry and various others.

One is a bottom-shelf book pairing in the store’s notable nonfiction section that you might not see anywhere else in NYC.

Displayed just above a policy book by Sen. Elizabeth Warren and another about Sen. Bernie Sanders, there’s David Horowitz’s “Big Agenda: President Trump’s Plan to Save America.”

That’s arguably an instructive pairing that you won’t see from a Brooklyn indie bookseller in “the bubble.”

But what’s also unusual there is not the book but the endorsement displayed below it. That endorsement comes from an Amazon commenter, who writes in part “Who is the Left? What is their agenda? How do Americans stop them?”

The commenter’s name? “Speak English.”

It’s a strange example of the internet coming to life before your eyes, with all its good and bad characteristics. And that’s a pretty good analogy for the promise and problems that Amazon and its physical stores hold.

Different from any bookstore you’ve ever been in

The new Amazon bookstore, the retailer’s seventh physical outlet and its first in NYC, even looks a little like a website: all the books are displayed cover-out so you might be walking through rows of thumbnail images.

The thumbnails are grouped not by author but by often data-driven subjects: “Books Kindle Readers Finish in 3 Days or Less,” or “Books with More Than 10,000 Reviews on Amazon.com.” There is a section for books the company knows New Yorkers tend to buy.

There are relatively few books: 3,000 titles in a 4,000-square-foot store. According to Amazon, the vast majority of the inventory is rated above 4 stars on Amazon.com, making popularity the guiding philosophy.

Almost every single book is also tagged with the product’s rating, number of reviews, and an “endorsement” from an Amazon employee or customer.

Sometimes that means sweet notes from happy buyers, such as Christina on an “inspiring” collection of stories from teachers called “Today I Made a Difference.” On other books there are inexplicable typos and banal reviews by Amazon employees, such as this review of Ernest Cline’s “Ready Player One”: “A lot of 80s references immersed in gaming culture, but overall just a expansive adventure.” (4.6 stars and 11,761 reviews as of Feb. 7).

It’s an interestingly democratic take on the “suggestion” cards typical for small bookstores: little notes written lovingly by book clerks, often in analog script. But it can also be a little overwhelming. When everything is suggested, nothing is.

One question the store prompts is whether it actually works as a bookstore. During a visit last week, a tourist from Tampa Bay could not find a book about investing because it wasn’t in stock. Another shopper needed a clerk’s help to look for a particular Bill O’Reilly book, because O’Reilly’s work is spread out in different sections.

Of course, the store was well-stocked with new hits and some classics, and the browser can always log onto Amazon and find just about any book in the universe there.

What’s Amazon doing in a bricks-and-mortar store?

This is the strength and beauty of Amazon — putting the breadth of human knowledge and production at everyone’s fingertips. You don’t need to be in that one city center with the amazing bookstore and coffeeshop to take part in cultural conversations. Maybe the Amazon breadth gives a Trump voter easy access to Warren’s book, and vice versa.

That possibility is a point of tension, however, between the store in Columbus Circle and Amazon’s online wearhouse. Online, you can indeed get anything, but that which is popular is further tailored to what you will likely like. Guided by algorithms, you’ll see mostly books recommended by anonymous buyers like “Speak English” or his or her lefty equivalent.

Amazon online probably doesn’t care much about your satisfaction or intellectual development as much as your willingness to stay within the entity and do all your consumption there.

That’s the other seemingly obvious reason the Amazon stores exist — to market and further all the other things done by Amazon.com. Including Amazon Prime, the company’s subscription service which gets perks like free shipping and cheaper prices at the Columbus Circle store, plus Amazon’s expanding technology ventures.

“This is table stakes in the electronics business,” author of the definitive Amazon book “The Everything Store” Brad Stone told me.

Maybe the hustle and bustle of the bookstore gets you in the door and you come out with a Kindle, an Amazon TV or Amazon Echo’s voice-prompted assistant Alexa, devices that take up nearly a quarter of the store’s floor-space.

In the end, you may find that Amazon satisfies your every need. Everything else is a one-star review.