[XorNot]

If any of those places were unhappy they would stop buying US treasuries. But they keep buying them.

There isn't a "can't be happy" feeling to a market - just what people actually do. At the scales and volumes involved, it is literally impossible for any of those countries to divest themselves of treasuries suddenly (for one thing, bonds don't work that way).

Moreover, governments only invest in real things. The productive output of the US is a real thing because all those places buy tons of US goods and services. Bitcoins are not real things. Perhaps moreover, why would any one of those places invest in a currency at a scale which would simply let them purchase the computing power to take it over permanently?

[iiAAIiajj98]

If an individual or group were to purchase the computing power to "take over" the currency Bitcoin would lose all of its value.

[XorNot]

Which perhaps should highlight why nationstates aren't going to buy it?

Because the money levels being talked about are large enough that you could trivially destroy it. Which means your entire foreign exchange rate is subject to whether someone wants to screw with the blockchain.

Which means at any junction, some third actor can hold the entire currency hostage - unless the governments invest in huge amounts of hashing hardware to protect it. Which is (1) a colossal waste of money and energy and (2) would, in turn, give them the capability to do the exact same thing.

Bitcoin will never be a currency held or traded by governments.