The problem is not the bourse, the problem is the exchange rate and buying up the US debt. Pill on the possibility of these three countries accepting "de facto" euros and we have a situation that I would love to analyze to know if a sudden drop of the dollar in front of the euro is more possible.
I do not have the number so I do not know. But in any case, the problem is not euros or dollars in a bourse.. the problem is what you do with the dollars you receive.
A pleasure I therefore claim to show, not how men think in myths, but how myths operate in men's minds without their being aware of the fact. Levi-Strauss, Claude
But it's a separate question. In the long run, we're all dead. John Maynard Keynes