Unsustainable.

You can't be me, I'm taken

... collapse and will either have to be replaced with something else or else Americans get used to living in a collapsed political economy (as Congolese did for over a decade before a tiny neighbor toppled the hollow shell, akin to the Maritimes invading and conquering the US).

I've been accused of being a Marxist, yet while Harpo's my favourite, it's Groucho I'm always quoting. Odd, that.