Agree completely with your points.

While I agree, its not like this is new. We already deeply interfere with markets....not just indirectly by setting interest rates, but directly by buying / selling equities via "plunge protection team" (ie. market stabilization) and the QE bailouts.

This raises a thorny issue: Where do you draw the line? Is it ok for a country to buy gold? oil? Where is the line between that and equities?

I suppose you could make the case that its ok if its just commodities and not equities....since equities have owners and shareholders and thus can be influenced, whereas commodities are indifferent to such things.