The Title "Also, Carthage must be destroyed" is a quote from Cato the Elder, a roman senator who would end every single speech of his with "Furthermore, I consider that Carthage must be destroyed." Or in latin, "Carthago delenda est."
@Romariel
Well, less cost and more the need for constant observation. Remember the locked box test. If they could lock it away and ignore it, then it would be safe. Anything that needs constant observation should be atleast Euclid.