UBS’ Art Cashen, a CNBC regular, clearly lays out the risks of contagion if Greece were to leave the euro zone.

Greek citizen (those who have not already done so) will withdraw their savings from the banks while it is still denominated in euros to preserve their purchasing power, not knowing what a drachma would be worth…

Seeing that, their Italian and Spanish cousins would likely do the same.

A classic bank-run is the risk, setting the European (and potentially global) dominoes in motion.

Still think Greece leaving the euro would be no big deal?