The shutting down of exchanges indicates that governments and/or banks are considering it a threat which is exactly what it's supposed to do.  (Or at least disruptive enough to create laws and regulations around it.)   You'll know that bitcoin is actually succeeding and growing when governments and banks start to put up a fight which is what we may be starting to see.  And attacking the exchanges are exactly how they'll do it.

No, the government certainly can't control the value or exchange rate.   But they can close down the shady shop on the corner where you cash in your paper lottery ticket.
Until grocery stores universally start to accept bitcoins, having 845 of them doesn't do you any good if you can't get anyone to accept it as currency.   Otherwise, it's just a meaningless number like the bankers and investors are suggesting.

For the near future, the exchanges are vital for fiat conversion and therefore adoption.   Regardless of the outcome, that battle is inevitable and an important sign the war is progressing as planned.