Why is Putin firing a hypersonic missile in Ukraine?

Putin, like many other belligerent autocrats, does like his Wunderwaffen, or ‘wonder weapons.’ Now it appears he’s even used one in an act of wasteful overkill in Ukraine: using the hypersonic Kh-47M2 Kinzhal (Dagger) missile to apparently destroy an arms depot in western Ukraine.

The Kinzhal was one of the six ‘magic weapons’ Putin unveiled in a moderately-deranged section of his 2018 state-of-the-nation address, which was memorably enlivened by a computer animation of what looked like a nuclear attack on Donald Trump’s Mar-a-Lago resort in Florida.