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And this is something where my technical knowledge is significantly limited. The whole topic about backdoors. I only know that most of what big corporations like Apple, Google, Facebook and so on and so forth have long been claiming about their privacy policies and that they would not cooperate with intelligence agencies, has all been refuted. Telegram claimed that their service is fully encrypted and no cooperation is ongoing with intelligence agencies, but there was proof not too long ago that it is a lie.
As long as centralized services or products like hard drives are used, what is the chance that all these things are coming with backdoors? Yet, assuming they have a backdoor and can read your hard drive and find private keys while you think they can't because it is encrypted, it would not be smart to let you know that they know as backdoors only work when nobody knows that they do. That is why earlier I said they would probably go after you in other ways via the tax law and not because you didn't declare digital value at the border. It will mostly be about target identification, subsequent surveillance and then whatever the law allows them to do.
The issue of backdoors into various hardware (or even into decrypting software) is beyond my own capabilities.
I have been considering if the method of encrypting is open source and solid, then it should not matter where such encrypted files are stored, they cannot be decrypted absent some kind of luck.. like trying to guess the location of one atom on the planet or perhaps one atom within the galaxy.
The one issue I still see is how are they going to design the law in the future that a guy at the border who carries in excess of $10,000 in cash is treated the same as the guy who carries in excess of $10,000 in bitcoin? Bitcoin is beyond supranational, and this is a bloody important feature of the network. No global legal framework will ever be able to dissolve the problems that nation states have with a currency they can't control. But there are still many, many, many people who haven't understood or don't want to understand that this is what strongly contributes to bitcoin's network value.
We all know that physical versus digital remains quite different so it is quite difficult to have parallels in the way that they are treated.
We already know that any single one of us can transport all of our wealth, or even the wealth of many others through one private key that can be carried in a variety of ways, and we can carry it anywhere around the world without anyone knowing or being able to figure it out, once they know, beyond perhaps beating us or charming us into revealing it.
It makes little sense to even conceptualize treating the digital versus physical the same... but yeah there still can be some interest in regards to how there might be any attempts to place controls on something like bitcoin at border crossings, and yeah of course, there are already a lot of tracking attempts and even increasing attempts at being able to monitor (and likely control) on and off ramps.. .which ultimate results in also trying to control individual ability to transact directly. which hopefully there will develop increasing resistance towards those direct transaction controls. Sure, there are going to continue to be casualties along the way and pretexts in regards to why it is for our own good to have third parties trying to intervene in direct transactions.
As soon as you access larger amounts of value outside your own country, it is possible that doesn't go unnoticed for very long
How many people are spending more than $10k abroad, without wanting a paper trail? If it's legal, like buying a car, I'd want a paper trail. If it's illegal what you're doing, it's no surprise they'll come after you.
Many of us are aware that the $10k limitations had origins that were in the ballpark of 50 years ago, so these kinds of limitations have been increasingly eroding at our rights to privacy and our abilities to transact... so I have troubles presuming that someone who is wanting to transact without paper trails in foreign jurisdictions with more than $10k is presumed to be "trying to get away with something." $10k does not go very far these days... Even normal people could easily spend $10k a month on somewhat normal traveling expenses..and surely in the early $70s, $10k would have had taken normal people more than a year to spend on somewhat "normal traveling expenses". So yeah, $10k these days is likely 1/12th the amount when those various $10k transaction (reporting) limitation rules were put into place.
I only know that most of what big corporations like Apple, Google, Facebook and so on and so forth have long been claiming about their privacy policies and that they would not cooperate with intelligence agencies, has all been refuted.
Now compare Protonmail or Mullvad: they can't share what they don't have or can't decrypt. Any good privacy service shouldn't keep records they can access.
I suppose that "we" (proclaiming to be non-technical folks) are somewhat reliant upon the claims of certain services (as the ones you mentioned) not actually having and/or logging data that pass through their services.