I am sure in the future when any form of crypto/virtual currency will take the lead there will be digital banks (even though it is totally not needed).
Virtual banking will be our reality just because banksters and corporation will make it look trendy and needed so people would follow.
The other one would be to totally ban bitcoin, and setup a spygrid tracking everyone who uses bitcoin and putting them into cages.
Assuming that such a situation could only takes place when mass adoption is taking place regarding bitcoin and banks can definitely feel the heat, publicly determined to eliminate such a service labeling it a scam and hence determined illegal. Idk how the govt can have the power to track every bitcoin user, I thought the btc technology promotes anonymity and protects users. Oh, and once such a mass adoption would be taking place, let's assume around 10 times than the population of users now, good luck trying to arrest 5-30 million people, maybe more.
They dont have to arrest 30 million people, its enough to arrest 100-200 of them to make an example and every other person will just obey.
Thats what always happens in any crime, if you were to arrest every person on the planet that has comitted a crime, no matter how small then the planet would instantly turn into a prison planet.
Funny though we already live in a prison planet, so i think justice has already been served...

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But joke aside, that is how population is controlled, you make an example of 1-2 people, then the 1 million other sheeple will be too scared and it will obey.