China tests deep-sea electro-hydrostatic actuator that can cut undersea cables at a depth of 3,500 meters

Not sure if there are any ships with 3500m of anchor chain....

They definitely don't need this to cause harm or cut cables as Russia has shown. So long as you know where it is, a ship anchor does the job just as well. Unless the US has some secret military base at the bottom of the Pacific only China knows about, this is almost certainly intended to save on deep dive time.

That is absolutely not how you use this quote... Whatever

America thought about vitamin D deficiency and decided to create and use two artificial suns.

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Literally a giant spool of cable on big ship, dropped into the ocean. And yes. They can get very thick, older copper cables would get up to a foot in diameter. Newer fiber optic cables are usually a few inches thick. Before the spool ends they use a second ship with another spool, splice the ends together and then swap positions. And just keep going until it reaches the other end. https://www.cnn.com/2019/07/25/asia/internet-undersea-cables-intl-hnk

They’re thick all right. Not straight though, they have optical amplifiers in them and also can split out. You might have a cable from the US east coast that connects at several points in Brazil and further south.

A cover story for what? Destroying infrastructure is easy, it doesn't require precision tools.

Performing a cutting-drag already is the first step first step in a cable repair. Then you perform two holding drags to bring up the two ends to the ship, splice in spare cable onboard, and lay the bight back out. For either type of drags there are specialized anchors to perform the cutting or holding. Repairs are routinely performed in deep sea locations.

I presume that’s why the Zimmerman telegram had to go through London?

Well a set of kitchen knives is a bit different than a multi-million dollar piece of tech that can be easily repurposed to cut off internet traffic for entire countries…

Yeah haha, the chain is at max 400 meters.

Well the thing is that the water around China(and the first island chain) is on the continental shelf, its quite shallow at most 200-300 meter. Of course when we leave the shelf(Eurasia continent) the depth just goes into the abyss.

Don't worry comrade ship is mostly empty internal volume is just to store worlds longest anchor chain.

No one is tapping at the underwater cable itself (with fiber). The days of tapping submarine cable was when they were all copper coax. It has been absolutely proven in some of Snowden's releases that Five Eyes countries were tapping fiber cable at the terminal land stations, but there it was with pre-built taps for them (things like Room 641A). It was much easier to do with coax because of the cable design, and easier to patch up afterwards (or even use non-physical detection techniques of the field surrounding the cable). But with fiber, the actual fibers are surrounded by, among other things, the copper power conductor for the high-voltage DC to power the repeaters and branching units. One couldn't get around not having to shunt the cable to gain access to the fiber. And even then, to install a splitter you still have to cut the fiber before splicing it in, which would immediately alert the owners, whose revenue is in the 1000s of dollars a minute for submarine traffic. Even boosting becomes an issue because of how sensitive these systems' optical power needs are. What's more, any splice and especially any amplifier (to cover up the degraded signal) are easy to detect with optical time-domain reflectometry by the terminal stations, which immediately would be run in the event of the aforementioned power and signal alarms going off. A COTDR trace would show the extra spike of the tap's repeater. What we have absolutely seen is state-actor involved sabotage and deliberate cutting of cables. Still, it is so much more logistically easier for an intelligence service to attach a tap on land. Where you already have the fiber out of the cable and aren't working right next to kill-you-dead voltages and leaving very obvious physical evidence of alteration to cable. All the more so, since we know that landings like those next to GCHQ Bude such tapping routinely occurs already.

Yeah one of the sea wolves has had this capability since the early 2000s

What possible reason would there be to cut a cable this deep? I see a "fishing" boat venturing to where they asked. Just like the fishing boats off Japan.

Yeah no shit and if you can read you’d realise that’d be 100% irrelevant to what they commented.

Vietnam, iran, Iraq, japan, japan, Afghanistan...

Large scale? Is Taiwan bigger than I remember?