The government may not like BTC, but what can they do against all it's users worldwide? How can one take over control? IT'S DECENTRALIZED!
Rather than the government, people should be worrying about the mining hardware race that's going on. That's something that could really end BTC for good.
But even in that case, not everything would be lost, we would still have litecoins (until they develop some ASIC for scrypt).

DECENTRALIZATION is what makes BTC what it is. Once we have fewer and fewer users in control of it, it's fundaments will have gone forgoten, and so it will become another history's footnote.