Thread by @Mauro_Gilli

Last night I read the Seymour Hersch's piece. I am probably late to the party and I am sure much more competent people than me have already take a stab at it, but here I wrote down a couple of points about the part on the activation of underwater mines.

Spoiler: it doesn't makes much sense.

If you haven't read Hersch's essay, here you can find it. To me it reads as a great Hollywood script, more than an accurate account of events. Below I explain why.
seymourhersh.substack.com/p/how-america-…

I will not focus on the detailed account of the meetings & similar. Despite being rather implausible (to start from the fact that one only source has all these details), this is not where the biggest problems are. Rather, with how the sabotage operation was carried out.

Let's start from how the US would have positioned the explosive devices. This is what Hersch writes.

This seems to be a really weird way of doing it. Organizing a "widely publicized" exercise (Hersch's words) in the very area you are planning a massive secret sabotage does not seem to be very smart.

You are literally calling for people's attention, and you jeopardize even the default plausible deniability that any perpetrator would have.

And this is particularly true when considering that many other alternative options, much more effective and efficient existed: such as having a special operation team reach the point with a fishing or commercial boat, thus nor raising anyone's alert.

Moreover, the idea of leaving these explosive devices for three months seems rather wild. Why run the risk that someone might discover them (e.g. during maintenance) or that something happens to the explosive devices during the three months?

Hersch addresses in detail this question.

But unless I misunderstood what he meant, his explanation doesn't make any sense. Explosive devices do not produce any noise. And even if they did, you wouldn't camouflage their noise by adapting them to the salinity of the sea.

My take here is that Hersch just wanted to impress his readers by mentioning something that has some affinity with reality (water salinity affects the diffusion of sound undersea). And so he just threw this idea there for show, without bothering much with substance.

Maybe Hersch meant that what needed to be camouflaged was the explosions - this is a generous interpretation of what he wrote. But even in this case, this sentence does not make sense, because, again salinity has nothing to do with camouflaging sound.

Moreover, ambient noise in the sea has distinct features - it's rather constant, isotropic, spread across a specific range of low frequencies & overall moderate in intensity - that are very different from explosions. Masking will not do much & salinity has nothing to do with it.

Of course, once you have placed the explosive devices, you will then have to detonate them. You could do it with a timer or with a remote command. Each has benefits and drawbacks. Hersch's account seems that the US decided that you either go big or go home.

Why release the sonar buoys from an airplane? An airplane can be detected by radars in the area and, unless the transponder is turned off, is tracked by aviation websites?

And in fact, back in September even someone like me who doesn't do any "OSINT" could notice and report the P-8 flying over that area

https://twitter.com/Mauro_Gilli/status/1575098748983660546?ref_src=twsrc%5Etfw%7Ctwcamp%5Etweetembed%7Ctwterm%5E1575098748983660546%7Ctwgr%5Eac7f73d30f0dc6e5c80665680147c0b55a83d566%7Ctwcon%5Es1_&ref_url=https%3A%2F%2Fwww.nzz.ch%2Finternational%2Fnord-stream-wie-kamen-die-lecks-in-die-pipelines-ld.1704868

And if you have to really drop the sonoboy from any plane, why use an anti-submarine warfare plane like the P-8 Poisedon, which is going to raise even more attention? Why not use a small commercial plan, flying just above the water? But more generally, why use a plane?

Moreover, an airplane might deliver the sonar buoy far from the pre-established point (wind, human error. ..) A fishing boat carrying special forces would do the job much more easily, cheaply and effectively, drop the sonar buoy exactly when needed without alerting anyone.

Hersch then describes the risk of accidental detonation. This seems an unnecessary lengthy discussion to say rather irrelevant things. If the ricever is set so as to recognize a specific set of signals, the risk of accidental activation by background noise seems rather low.

Hersch's discussion is tantamount to saying that because in Times Square, there are massive electromagnetic emissions (I could have said light, but would not have been Herschesque), your car door might accidentally be opened by them...

Or, to use another example, think when you use Shazam to identify a song. How likely is it going to conflate the sound of your dishwasher for Beethoven's 9 symphony (thanks @RM_marco01 for making me think of this)?

Again, underwater sound has very distinct features (first of all in frequency band), so the risk Hersch poses seems really bizarre. But what is the solution that he discusses? A sequence of unique low frequency tonal sounds.

I am not an expert in underwater sound communications, but a couple of points seem warranted. Since the buoy would be just above the explosive devices, why use low frequency sounds? It seems it provides no real advantage, and only disadvantage.

As a reminder, the explosion took place in a rather shallow part of the sea, at about 80m depth. 80m shouldn't pose any significant problem for a high frequency sound.

It offers also a key advantage: it travels much shorter range than low frequency sound. This means would less likely get detected by other countries (low frequency sound travels longer distances, think when you leave a concert, and you can still hear the basses and the drums...)

Summary of all: if the CIA had hired me to run this operation, I would have come up with a much cheaper plan that would have raised much less suspicion.