You're saying that there is no threat in accepting Euro? There definitely is - as you said, investors don't like uncertainty, and in our specific case that makes great uncertainty. Imagine a country saying they will abandon their 100+ years old currency in favor of much younger and worse performing one that the country has no control over, forever tying it to risky economies. Union currencies have usually been formed in times of either crisis or rapid growth which of course changes the risk calculation, but we're somewhere in the middle between these two and not after any destructive war.