In the mind of Kim Jong Un, “prestige” is all about spectacle – events in front of enormous crowds, gilded palaces, huge ceremonial parades, and showing off military capabilities. Think “mini Trump” and you get the idea; it’s the same mindset. To have the latest and greatest navy warship – which this desperately poor country could ill afford to build in the first place – slide out of the shipyard and fall over must have been unimaginably infuriating for Dear Leader.
I believe every year there’s an event for big sailing ships. The USCG cutter Eagle takes part in these. I spent over 2 years living and working on Governors Island, which then was the largest US Coast Guard base, in the New York harbor. We never saw the ships from there, I guess they went down the east side of Manhattan.
Could have called it a submarine and declared it a success 
Maybe.
The signature useful feature of a submarine is not that it goes underwater. It’s that it comes back up again. 
Not every year, but they happen. Boston did a tall ship gathering in 2017 that I volunteered at, and I’m hearing about another in 2026. I’m pretty sure that nearby cities coordinate on these, so other east coast cities may do the same next year. I seem to remember New York City having similar events in 1976 (as part of the Bicentennial), and to celebrate the refurbishment of the Statue of Liberty. No idea what route they take, or where they moor, but they must have passed Governor’s Island on the way in and out.
I was just discussing Governor’s Island with a coworker who grew up in Brooklyn. Is it still a Coast Guard station?
That shut down around 1995.
The subsequent history is complicated but the island is now a combo of National Monument and NYC city park. And a bit of a white elephant from the city government POV.
Governors Island - Wikipedia is pretty thorough.
I met someone who teaches in the public high school on Governor’s Island. She said that it’s a trek, but a good school.
Two questions on the school website are “Would I be willing to travel to Governors Island every day?” “Are you okay with a long commute?”
10 or 20 years ago I watched part of a documentary about post war Japan. It included an interview with an engineer responsible for the first post-war large ship out of a shipyard, in which he recounted that if you looked at the launch film clip, you could see the handle of the knife in his sleave. And they showed the film clip, and you could see the handle of the knife, which he had so that he could commit suicide if anything went badly wrong with the launch.
Isn’t that what they call “torque”?
Never mind.
I see, so not the same as torque then. Thanks for the explanation! I read it before you deleted it. It vanished while I was looking at it.
Curious as to what the explanation was. I always understood prop walk to be a complex phenomenon into which torque has a part to play, but mostly I don’t understand it. I just know that different boats I’ve said have exhibited walk in different amounts, sometimes different in forward vs revers.
Short version is asymmetric water flow impinging differently on the left and right sides of the hull produces a net force one way or the other that shoves the vessel sideways. Generally a larger effect in reverse than forward. Akin to P-factor in propeller-driven airplanes.
This is a pretty good article: Propeller walk - Wikipedia.