[oleganza]

That would be very expensive for government. First, it will basically give away a lot of money and invite 100 times more people and capital in the bitcoin economy. Then, after selling its stash it will affect the price much less (because it will also have been driven up by many additional speculators) and simply earn back much less USD than they have spent.

Of course, it will destabilize prices for some period of time, but only at great expense to itself and making millions of people aware of Bitcoin and thus accelerating its long-term growth.

[maxerickson]

You are saying you don't think government manipulation would have negative (long term) impacts. That's a separate thing from the government not being able to play games with the currency.

Part of the reason I said 'a few billion' is that several governments can afford to spend that, no problem. If they think they are facing an existential threat (as you seem to believe), it is basically a certainty that they will try it.

[oleganza]

As a speculator the government is no better than any other speculator. It will compete on par (more cash is simply more risk). And big players trading bitcoin is a good reason for many more players to jump in this market. The governments are unique in their ability to apply guns. When guns are not used, it's no different from big investment firms playing on markets.