Their reporting goes pretty deep and their renderings/animations are usually very well made, and this was no exception: https://www.nytimes.com/2021/03/24/world/asia/tankers-north-...
This is already basically there, but the real-life ramifications for the people in these regions undercuts the enjoyment of the tech-political drama.
Arecibo was until it sadly collapsed last year, not just a large radio telescope but the largest radar disk in the world. Larger radio telescopes lacked that feature. In space you could exceed it without the obvious scaling issues of such a large structure and its weight.
You also have heat as a problem. That space is cold is a bit or a misnomer. The problem with space is that its a near perfect vacuum so things tend to stay the same temp unless they are in direct sunlight. And if they are its hard to dump that heat.
With appropriate thermal imaging it would be pretty easy to tell a spacecraft apart from rocks because it will be making its own heat. Since radiation is the only reliable form of losing that heat you need large radiators on your craft like the ISS has. But those run contrary to good stealth design practices.
There is also the matter of orbits and how natural objects simply aren't going to have certain ones so no matter how innocuous you may look, if you are taking a path only a spacecraft would take nobody is going to be fooled.
Note that this is for strategic level stealth, which is to say your enemy doesn't even know you're in system. Tactical level stealth is vastly easier, and can be as simple as launching several hundred thousand heated decoys into system before entering yourself - one of these is the attacker, can you find which?
This last strategy is actually what we'd implement if ever anyone tried to seriously develop anti-ICBM technology.
... but for a more serious thought, and to trend deeper into hard sci-fi: you can have a lot of fun with questions like "How good is the technology to identify solid objects in space that are intentionally minimizing their radiation exposure?" You don't even have to go too fancy with stealth-coatings or Star Trek cloaking-devices; a challenge of modern astronomoy is that shipping-vessel-sized rocks in space are very far away, reflect very little radiation, and can be moving extremely fast. Do the authorities monitor space with optical equipment, or do they have the resources to solve the distance-to-target problem by blanketing the space they control with a network of ships or sensors? Such a fabric would probably be the saddle-point between cheap and effective if they could be mass-produced.
You can also have fun with propulsion. A ship "on the drift" can be much darker than a ship undergoing maneuvers... And it can even stay dark in the direction it's accelerating if it's using cold exhaust fired away from the observer (or if it has a lot of time to maneuver and does so by firing photons away from the observer, which will only be visible if they reflect off something behind the ship). This gets into a very submarine-combat feel, which the videogame "Objects In Space" explored.
Interesting idea I don't think I've seen in sci-fi before is deploying a grid of small satellites in to space where all they do is measure the distances between each other. Then any objects passing through the grid gravitationally disrupt it, and depending on how accurate the distance measurements are (and how much math you can do to account for other gravity fluctuations), you could hypothetically get a fairly impenetrable safety net if you stick to hard-science and ships can't create antigravity effects at range... A smaller-scale experiment like this involving two satellites orbiting the moon is how NASA mapped the mass concentrations resulting from meteorite impacts that disrupt the orbit of lunar satellites (and the trajectories of landing craft).
Imagine non-propulsion. Selectively make one side of your ship ninety-nine percent black and the other side ninety-eight ... wait for light pressure to do its job. It's slow but damned if that wouldn't be difficult to detect as a method of making maneuvers.
It's literally my favorite science fiction. I also recommend purchasing and reading at least the first half of the series. The latter half of the series go into a lot more political fiction instead of science fiction but it's definitely worth reading if you like the political story that develops in the middle of the series.
- Africa has been hit hard, with fishers losing at least 40% of income (although here these ships do seem to have some sort of license): https://www.spectator.co.uk/article/how-china-s-fishermen-ar...
- North Korean squid populations have been depleted so hard by Chinese vessels that Japan and South Korea felt the impact in reduced fishing amounts: https://foreignpolicy.com/2020/11/30/china-beijing-fishing-a...
- The Philippines even reported "permanent structures" having been built on coral reefs to support illegal fishing: https://www.9news.com.au/world/south-china-sea-dispute-phili...
Chinese fishermen have a record of ramming foreign coast guard, and even military ships of smaller countries.
One thing that article made me think about is the morality of indicting shipments between two willing countries with ocean frontage. It's been a thing ever since bluewater navies got invented, but strikes me as having a sketchy ethical basis.
Might make it harder to establish the size of crates on your ship with ultra high resolution SAR, but you certainly wouldn't be hidden .
I have seen several sailing texts explicitly recommend the use of a retroreflector to improve the radar visibility of small fiberglass vessels.
That smells of "if you have nothing to hide, you have nothing to fear"
Fun fact: a significant part of the Lockheed Sea Shadow program was wake suppression.