But to say that the rest of the world had 'no choice' is simply not true. Of course it had a choice.
You can't just disconnect yourself in the modern economy. The increased contagion is not a choice, it's a result of technological advances.
That I can now work from anywhere in the world and bank elsewhere so easily is nobody's choice, it just happens, the internet and the increasingly small world happens.
The world is connected to each other financially not because of their decisions but because this is an inherent byproduct of technological advancement.