By what mechanism? The whole point of bitcoin is that you can’t force a consensus change. This is enforced by the algorithm and the laws of thermodynamics.

What you can do, and what has been done in the past, is get a critical mass of large cryptocurrency actors to agree that a protocol change should be applied and that the results of that protocol change are called "Bitcoin". As the Bitcoin Cash folks quickly realized, it's not tenable to try and maintain a disagreement with Coinbase and large miners about about what the Bitcoin protocol is; if you don't want to accept the upgrade, your only practical option is to make a fork and call it something else.

If, for whatever reason, all the mining power switches to the other chain, it will become the de facto "Bitcoin".

I don't know what the specific mechanism would be, but I would bet that it relates to the billions of dollars backing the current ecosystem, and the interests of the people behind them. If the right event or crisis comes along, then people could be compelled to switch over to something else.

I'm sure there's someone out there still mining blocks on that chain with the exploit from 2010, but that's not where the mining power is. If the right series of events occurs, the miners will switch.

> If, for whatever reason, all the mining power switches to the other chain, it will become the de facto "Bitcoin".

The miners do not control the network. The people transacting on the network control the network and decides who is rich and who is not; and whether the miners get paid or not.

If literally 100% of miners switched, leaving zero on the original chain, then people will have no choice since it won’t do any more transactions.

But if, say, a mere 99% of miners switch, it’s far from a given that people would follow. Having more mining capacity makes the chain more secure, but it’s not that big of a deal.

And anyone can become a miner. It's not reasonable on small rigs because there are so many miners now, but if most of them leave, then the common man can get back in to mining.

There is an interesting failure mode, though. Bitcoin is supposed to adjust mining difficult every two weeks to maintain the pace of roughly one block every 10 minutes. But that interval is based on block count, not time. Adjustment happens every 2016 blocks.

If miners suddenly fled en masse, it’s possible for the chain to be left stranded where the small number of miners remaining couldn’t realistically get to the next 2016-block interval to adjust the difficulty down to match the drastically decreased mining capacity. If mining capacity dropped by a factor of 1000 and it happened right after an adjustment, then bitcoin would be producing about one block every week, and it would take about 40 years (if mining capacity stayed constant) to reach the next adjustment.

This is well known and studied. I’ve produced and field tested an alternative, close to optimal adjustment algorithm and the code for a soft-fork transition. This could enable a set of miners to get “pre-agreement” on transaction ordering in an out of band forward block chain while they work to fight down the difficulty of the old chain.

https://freico.in/forward-blocks-scalingbitcoin-paper.pdf

Bitcoin has forked a few times it's creation: https://en.wikipedia.org/wiki/List_of_bitcoin_forks The determining factor for which fork is successfully is bases on the Bitcoin node runners and miners choosing which fork they devote their resources to.

Governments around the world are 100% attempting different plans to destabilize or destroy Bitcoin because it harms their interests and ability to print money from thin air. But at the end of the day it's a distributed ledger, so even if they do find a way to manipulate or damage or takeover the network the Bitcoin users can just fork it from before they did their damage and continue from there. That is the ultimate power of a decentralized blockchain, nobody has ultimate power and everyone votes with their resources.

If anything, the real risk of BTC isn't governments destroying it.

It's that everything you do on the blockchain is there forever, so if a government needs you in jail for using it, they can show you were involved in a financial crime and the blockchain proves it... And if you are unwilling to give up your public wallet they can keep you in jail indefinitely until you do.

Bitcoin is pseudonymous, not anonymous. Every activity on the network is encoded into a perpetual auditable dataset, by design.

That sucks, because what if that wallet is completely destroyed? :S

Power comes from the barrel of a gun.

Yes. That is why the Second Amendment is so important. It reminds those in the government not to overstep their bounds.

Got some specific recent oversteps that were prevented by armed citizens in mind? Or are you just talking about ancient history or on-paper theory?

The government in the US has far bigger guns than the citizenry these days.

The only thing that will ever prevent a government from abusing its populace is the willingness of actors of the state - police and soldiers - to say no to abusive orders. Independent thinking coupled with believing in the people more than the executive is the only thing that will ever keep us safe. Guns are not defensive tools. The state can shoot you before you shoot them if they decide they don't like what you're doing.

Put guns in the hands of the people you're policing and you just make it that much easier for the police/soldiers/govt sympathizers to make it us-against-them and side with the totalitarians.

> Got some specific recent oversteps that were prevented by armed citizens in mind?

I guess arresting ten thousand people a year for grevious hurting of the feefees with assault tweets is a recently prevented overstep that the citizens of some other countries have not been able to prevent.