Overlooking the finer point that if any entity or government *could* theoretically buy all existing bitcoin with the goal of making it worthless and irrelevant, and were they to theoretically succeed, then at the end of the day, they would've just wasted huge sums of money in the process...their fiat is gone in exchange for btc which is also no longer worth anything. Lose/lose/
Only a dumbass would do that.
So, I figure the US government will be making plans any day now to do just exactly that