That sounds really horrible but no country will do that with their economy only to control bitcoin. With that limited supply of bitcoin government can try to gain control over bitcoin and make it manipulated, but no one would dare to do that.
There are governments known for printing each other's money on agreement and some known for printing currency of other nations without their control or say (it's been a fairly common war tactic in the past). Most central banks try to control inflation, if you get a country whose inflation goes negative or below target (like the UK/EU do a lot of the time) then there's a chance bitcoin's price could pump if they step in and do something like offering low interest loans, to buy back their own bonds or to buy shares in companies in that county (thus allowing those places to have a greater amount of free cash they can use to invest in assets).
It could happen at a small exchange with 100 people but it won't happen when there's 100 exchanges with 500+ active traders on each of them.
If it did happen with a lot of people I wonder who would actually be in control of that situation. A troll anywhere could probably cause the price to crumble and force a lot of people to sell really low (there's obviously almost no chance of this happening but it's probably another reason why it wouldn't - a situation where everyone tries to manipulate the market might light to a situation where all the exchangers are just manipulated into selling lower).
