>The US is so developed, that even if the country was completely cut off from the world and operated as an internal economy it would still remain the world's largest.

That's a pretty enormous assumption. The US economy tends to crash into a smouldering ruin on the tiniest fluctuation in the inputs. The notion that you could abolish 27% of the real GDP and everything else just continues is not reality based. The US is barrelling towards a natural debt limit and that alone is going to be utter catastrophe for an economy that is fuelled by an insane amount of debt spending. The fact that some of the cons, like Trump and Graham, are trying to extract as much as they can as quickly as they can is telling enough.

The US economy is a tenuous mirage. Like Americans constantly love showing the fun charts demonstrating that various backwater, poor, Methville states with negligible business or industry have a higher GDP / capita than most developed nations. Sure they do.