We often underestimate the ease with which terrible disasters can accompany our efforts and enterprises.  Vigilance tends to lapse with routine; and with time, even the most dangerous cargoes may begin to look benign.  Any nation wishing to handle nuclear materials enters a kind of pact with the devil:  in return for power and prestige, it can never forget what it is dealing with, and it can never let its guard down.  Two lines from the Roman poet Lucan (Pharsalia IX.1020) expresses this idea well: