Like other winner-take-all markets, it splits into multiple winner-take-all markets when their are natural (or let's say "national") boundaries. Note that we d

Like other winner-take-all markets, it splits into multiple winner-take-all markets when their are natural (or let's say "national") boundaries. Note that we don't still have deutschemarks, francs, guilders, schillings, lira, peseta, and escudo, though. The network effects of having a single currency are big enough that 19 nations were willing to give up their national currency.