The only scenarios I can conjure are two: A catastrophic event that eliminates all electronic devices on the planet simultaneously,
It can still be restarted, even if the entire electronic sector gets hit by a massive solar flare, if a few honest people kept a backup of the blockchain in a DVD, then the internet, and bitcoin can be restarted anytime.
Now the havoc will be huge and bitcoin's price will temporarly hit 0, but after it's restarted it will go back again, after all its not bitcoins fault.
I`m more worried of the bank accounts and havoc in the economy that this can cause.
and the possibility that the bitcoin protocol and cryptography is "broken" either by exploitation of an unnoticed bug or by the invention of a Quantum Computer that is able to overwhelm the system in every way controlled by attackers.
Quantum computers are not a real danger for the forseeable 40-50 years. Even if a hyperfast quantum PC gets invented its still reasonably safe to hold bitcoins this way.
A bug could be, but i`m more worried of corrupt bitcoin core clients being downloaded , by somebody hijacking the bitcoin.org site.
Although a stuff like that can easily be detected and people will be notified.
Massive world wide exchange hacks, every exchange and online wallet provider.
A coordinated global hack of all exchanges and online wallet providers is unlikely, since they have different security equipment, its like coordinated hack against all bank accounts. Bitcoin is not a political enemy, yet, so its not in the target for now.
People loose interest and move on, no transaction = no fees, miners pull out, blockchain stops.
Thats silly, they wont lose interest, since constant innovation comes out every day. Plus they are invested in it, its like saying you leave 1000$ in a box, then you lose interest and never take it out from there...
Most crypto investers wiill just move to another coin i think.
Saying this i still don't think bitcoin will die anytime soon.
The only risk I can think of, which is the biggest risk is either:
- Outright ban in the major hubs -It will shrink bitcoin back to small price and send it to the black markets
- Massive regulation & taxation worldwide - It will slow down progress, but it wont stop it
- Bitcoin 2.0 comes along with totally anonymous transactions & better security (1024 or 2048 bit protection) - Monero,DASH, and others are pretty big competitors and one day could take over
Out of these 3 bigger risks I highlighted the BITCOIN 2.0 is the biggest risk currently bitcoin has, innovation will destroy replace bitcoin eventually.
I don't think outright ban will happen now, banks love it due to regulation arbitrage, politicians love it because they can get more ***political donations*** due to bitcoin's semi-anonymity. Nobody left to ban it.
Regulation is a concern now, but it isn't as bad as you would have imagined. Yes Bitlicense has drawbacks but atleast it gives legitimacy to bitcoin, and maybe wallstreet will start respecting it.
Be that 2 years or 50, who knows but I`d invest some in Monero now and find out later
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