The failure was with Mt. Gox. Not Bitcoin.
The point you are missing is that Bitcoin can't be controlled regardless of what the government wants to do. They can try to control people but they can't control Bitcoin. They can try to prevent you from buying it by going after the exchanges but there is nothing they can do to stop you from transacting with it. It is a world wide currency. It can be transacted with through encrypted channels which protect your identity. It is a tactic which can be utilized to thwart tyranny. Using it is an act of rebellion. The more people that use it, the harder it will be for them to stop it.
So are you telling me that your answer to the question....
If we must have a fiat currency that is backed by nothing, why shouldn't it be Bitcoin?
....is "because my government masters don't like it" ???
Other than mindless comparisons to tulips, the most common reaction to Bitcoin I hear is "I am too scared of what the government thinks about it"
Thank God our forefathers didn't think like some of you people.