In his history of the Peloponnesian War, the ancient historian Thucydides spends much time describing ships: how many ships each side had, what the wind was like on the day of the battle, how the ships were fitted. Naval power and control of waters often constituted the difference between victory and defeat. The ancient Greeks built navies to protect their cities from pirates and defend sea trade routes, but they also emphasized naval power because Greece’s dispersed geography makes it highly vulnerable. Defending even smaller islands required ample ships, manpower and supplies.
Greece is not facing any invading force, but the challenge of geography remains the same. Even with the best equipment and resources — which cash-stripped Greece does not possess — it would be a difficult task for Greece to intercept every refugee boat entering its waters and ensure that all of its passengers remain, over a period of weeks and months, fully accounted for, registered, housed and fed.