There are 19,118,068 bitcoins in circulation. 21 million is the total supply when all bitcoin have been successfully mined, the time this would take is estimated to be till 2140.

There would be no poor bitcoiners. They would have all sold to the state government.
The possibility of this happening is low. State governments is not a Global entity, and buying out all bitcoins for the name of bitcoin to die off seems pointless.

They would also need majority to be willing to sell, including Satoshi.

- Jay -

A couple questions to your theory OP.

I hold a part of that 21 million. How would the goverment buy my coins? There's many bitcoiners around the world who wouldn't sell if they saw aggressive buying from a party, in this case a government.
It's the same kind of situation as if you owned a piece of land worth $100k and all of a sudden somebody came and offered $300k to buy it. You'd think they know something. Maybe there's oil or some other natural resource? Maybe there's a plan for a shopping center to be built and they want to flip the land for even more than they're offering you?  

What about people who have millions and don't need fiat now? If someone came and gave them 50k USD for a bitcoin they wouldn't sell and if the same party came a month later offering 100k they also wouldn't sell. Holding money that's safe from inflation and surveillance maybe more important to them, since they already have 10 million in real estate and another 10 in stocks.

There's no single entity like a government or a company that would be able to buy bitcoin at this point. All they'd do is buy what's available on exchanges and drive up price to insane levels like a million USD because if you'd reduce coins on exchanges by 80 or 90% you'd introduce insane volatility. You'd have bitcoin swing to 100k and back to 50k daily.

I don't think there would be swings, I think it would be a continued climb. If the government(s) were not telling people they were doing it, just buying and holding it then as the price REALLY started to go up due to the lower amount of coins being circulated people would REALLY have FOMO and the price would just keep going up.

Right till the very hard crash at the end.

But I can't see any government bothering to do it, or being able to keep it a secret as they spent that much money doing it.

-Dave

Man can you at least read the first page of replies and see how quickly you'll find sweeping statements like this to be wrong.

Even if all coins were already in circulation and in a single wallet, the total value isn't the figure you think it is.

Might want to look up your country's budget and see what they're spending on, say, if I'm guessing right where you're from, religion.

More accurately, please!

There are only ~ 21 millions of bitcoin in total supply. Not all of them will be used by people on Earth. Many of them received from mining from block rewards and lost forever (by losing private keys in early years of Bitcoin network).

It can be done by a consensus in protocol but it won't happen. I strongly believe that it won't happen because the current total supply creates value for Bitcoin. The Bitcoin community don't have reasons to vote and increase total supply of Bitcoin.

• How is the 21 Million Bitcoin Cap Defined and Enforced?

There are many Bitcoin forks but they are not real Bitcoin. There is a unique Bitcoin, the original one with ~ 21 millions in total.

• How Many Bitcoin Forks Are There? You will be surprised!!!

To buy, they must buy it from sellers. Do you think governments can be sure that they actually buy all bitcoin from non-governmental holders?

It's not possible for the government to buy all the 21 Million Bitcoin.
1) The governments already have enough on their plate and the world economy is in mess. I believe the best thing a sensible government will focus on is how to fix their backyard issue not the accumulation of all 21 Million BTC.
2) We have the early and long-term holders of BTC who are not planning to sell any portion of their bag until the total 21 Million coins are mine.

It is good you understand this, which show that it is impossible for the governments to have all the 21 Million BTC and the number of at least 1BTC holder was said to have increased lately.

It's impossible in reality. Also if a particular government buys all 21 million supply from the market, then the price of the bitcoin will turn back to zero because there will be no seller in the market. So the market will be straight away crashed to zero. One basic parameter of bitcoin is its decentralization, once it's gone, the foundation of bitcoin will be destroyed. So no government would try to do such a highly costly adventure which will eventually turn back to zero.

Bitcoin's price is based on demand. So if there's no seller in the market, buyers will eventually move out of the market and will look for an alternative. So probably a new coin will rise to fame if bitcoin is purchased by government and kept under safe custody. Overall, it is an imaginary situation which will never ever happen. At least not in our lifetime!

Well, Bitcoin won't be fully mined for the next 100+ years so thats not a problem we have to care about all that much. And even if the government decides to tackle Bitcoin buy buying it all up, thats fine. The "free" Bitcoin which is not in the governments hands will be worth a lot more. So if the government wants to help us, thats a great plan.

And what are the governments going to do about the altcoins? We seem to have quite a lot of those. Has the government thought of a plan for them yet?

I think nobody has the power to control or restrict Bitcoin in any way except at the end-node. Like a business which accepts payment in Bitcoin, for example. You can ban that business from accepting Bitcoin. Because that business is centralised and they know who owns it.

I don't think there's even a plan for that, it already escalated worldwide and I don't think all government in the world would ever keep it on them. If they can take it, it will surely by force, the thing is they should have to buy it instead of using it in force, I wonder if they wouldn't see a protest if this happen.