They'll be about as much of a threat as Mintchip was.  We already use digital currencies supported by the authorities of every country, it's called having a bank account.  Whatever they end up creating will have literally no perceivable benefit to anyone beyond what we've already got today.  No system with an unlimited monetary supply, central points of failure, and inherent shortcomings with fungibility and censorship (which is exactly what they'll come up with) will look like it's worth anything compared to Bitcoin.  All they can do is create a pale and crippled imitation.  There's no contest.