As someone who's not American nor European (but lived for a while in both) this self-satisfied approach always amazes me. Are you guys realizing where you're heading?
Europe: "Whatever, everyone here is middle class, self-fulfilled and happy... Forget about balanced budgets, unemployment and negative interest rates..."
Rest-Of-World: "Dammit, I just want to survive..."
It made sense in the late 1800s, when foreign potentates exporting friends and family members and sponsoring their efforts to become rulers abroad was more of a thing, and the US was a young and not well-established country that might be particularly vulnerable to that.
Its arguably outlived any reasonable need, but at the same time the US has developed enough cultural nativism that, combined with the by-design difficulty of amending the Constitution, its difficult to change.
Schwarzenegger's lack of a strong political base is a bigger factor there, which is why his only route to getting in office in the first place was exploiting celebrity in a way that would not work in a normal election in the Gray Davis recall that was largely funded by Darryl Issa as a way to get Darryl Issa into the Governor's mansion (California's recall system combines a majority vote to remove with a simultaneous plurality vote on the replacement-to-be-installed-if-the-removal-succeeds, and has no primary election to narrow the field of candidates -- this makes celebrity name recognition a bigger factor than in regular elections, and allows [as in the Davis recall] a replacement candidate to "win" with less votes than were cast to retain the incumbent.)
He did manage to get reelected, but the calculus of a party turning on their own incumbent is different than that of getting behind a candidate that isn't an incumbent.
Even if an unusual thing happened in national politics that enabled that approach to work again (there's no equivalent "Presidential recall", but the 2016 Republican Primary shows that even with a regular primary, sometimes forces align in unusual ways), the "celebrity political outsider" thing really only works for one major office, and Arnold had already used his shot on that. After that, he was a veteran politician that still lacked a strong base even in his own party.
You can forget about balanced budgets. If you print a currency you borrow in, you never have to worry about insolvency. Ever.
Unless you're one of those kooky economists who predicted Japan would experience full on hyperinflation in the 90s. Then again in the 2000s. Then again in the 2010s...