Man I wish I were as optimistic as you are.

I mean you do know what is used right now instead of brain scanning right? "Special Interrogation techniques"? Torture, we torture and mentally break people (with serious physical damage in the process) and then go from there.

Is it effective? No, we've known that torture is one of the worse interrogation tactics, and that it leads to more lies tha anything. But that didn't stop the US from upping its use in the early 2000s.

Could governments use this to do interrogations? Probably. But they also have a high chance that they'll keep using torture instead. Because the reality is that there's an advantage of returning friends and family that have been broken deeply. If governments switched to just reading the mind instead of doing "anything the ends justify" it would be an improvement.

I do think that the biggest risk is what people would do in this panopticon, out of desperation and fear, leading to a lot of escalation. See Black Mirror s3e4 Crocodile for an exploration on the subject.

Also you have to understand the challenge of how this tool works. It's as good as reading minds as lie detectors are at detecting lies.

First you have to calibrate it. This is two studies. The first study had someone type in the keyboard some known sentences, and then they measured the mind as they were typing. A computer eventually was able to map thoughts to the typing. The second study took a focus on the areas of the brain that we know are bound to language. Again we can't form the thoughts for any random person, but we can identify common patterns that could clue us in to how these things work.

It also can be used to help people that can type but cannot talk (or will not be able to talk in the future) to create a mind-to-speech system.

So first we have to build this to something that can read any arbitrary mind, if it's possible.

The second thing is that because of how this works this is identifying not random thoughts, but things that people want to express (by typing it). So we wouldn't be able to read thoughts that people have in the background. There's a lot of questions on that, and we know that some people think in sentences, but not everyone has that "voice" inside their head.

The third thing is that this works under certain assumptions of how people work. Just like a lie machine works on the idea that after calibrating the machine people will react certain way, this machine would work on the idea that after some calibration, people's mind think certain way. Knowing how this works it would be easy to hijack it, both by hijacking the calibration phase (the easiest for lie detectors) and also by hijacking the assumptions when things are working. So for example you could be thinking of a certain mantra and repeating it in your mind in the background (it requires training, but anyone who knows how to meditate should be succesful at it) could be enough to throw any mind-readers for a loop.

More worrisome is the power of propaganda. Honestly the way this tech could lead to a dystopia (which would quickly implode) is more "Brave New World" and less "1984". Imagine ads that are able to read your mind and see how effective they've been and adapt until they are able to manipulate you perfectly at a low neuronal level. Basically ads that are able to make you addicted to anything.