> If it had the stability of entire countries behind it, it wouldn't fluctuate this much and even if it did, if everything's in that currency then you don't notice it in daily life either.
Common misconception. You basically need currencies tied to countries (more precisely, OCAs or optimal currency areas, characterised by either 1. homogeneity with respect to external shocks (not the case e.g. within Europe), 2. complete factor mobility (not the case e.g. within Europe), or 3. transfer payments (that is, fiscal support)).
In other words: If there were one currency (only), even with the stability of entire countries behind it, it would still fluctuate too much to be very useful. Or, to put it different again: You need FX. One currency is not enough.
Common misconception. You basically need currencies tied to countries (more precisely, OCAs or optimal currency areas, characterised by either 1. homogeneity with respect to external shocks (not the case e.g. within Europe), 2. complete factor mobility (not the case e.g. within Europe), or 3. transfer payments (that is, fiscal support)).
In other words: If there were one currency (only), even with the stability of entire countries behind it, it would still fluctuate too much to be very useful. Or, to put it different again: You need FX. One currency is not enough.