The Federal Reserve; the people who own the US government(and the mightiest military), have much to loose when bitcoin goes global mainstream.
We are starting to see some possible tactics with recent statements by fraudster fed associate Jamie Dimon.
Asside from turning off the internet what else are these thieving pricks likely to do?
Don't worry. The government cannot shut down bitcoin the same way they shut down LibertyReserve because in order to do that they would have to shut down the entire internet, and that is impossible and unfeasible for the government.
Of course they could technically make bitcoin illegal in the country, or make bitcoin exchanges/trading illegal.
But then, who would comply? There is really very little way they're going to find out, especially if you are trading irl, p2p style.