This is something which I've beleived for awhile, which is the prospect that if big governments and banks worked heavily together they'd be able to remove Bitcoin from the face of the earth. They wouldn't ban it, as that would be a tough thing to swallow for the American people as they wouldn't see a good reason to do that ( at least in my mind here) But they could just go ahead and regulate Bitcoin into oblivion, making it hard for Bitcoin businesses (buying and selling, trading, etc) to operate within their countries, or be subject to insane taxes, KYC AML and such.
Do you think Governments could kill Bitcoin?
Well, there is 16.985.737 BTC supply around the world right now, IF ...IF 1 government want to spend their money to buy all of bitcoins, and keep it for themself to bury it, maybe they could stop bitcoin. But, who want to spend that large amount of money just on one thing???