You can't just shut them down... But you might be able to effectively halt their use by making it much harder to transfers money out if the ecosystem by making

You can't just shut them down... But you might be able to effectively halt their use by making it much harder to transfers money out if the ecosystem by making possession of them illegal. I'm strongly anti-crypto but I don't support trying to ban them. I might support a middle ground such as requiring people to be accredited investors to buy them, depending on the details.