The Prince by Niccolo Machiavelli Chapter 10 Page 3

them are protected by moats and suitable ramparts, are well supplied with artillery, and keep their public magazines constantly stored with victual, drink and fuel, enough to last them for a year. Besides which, in order to support the poorer class of citizens without public loss, they lay in a common stock of materials for these to work on for a year, in the handicrafts which are the life and sinews of such cities, and by which the common people live. Moreover, they esteem military exercises and have many regulations for their maintenance.

A Prince, therefore, who has a strong city, and who does not make himself hated, can not be attacked, or should he be so, his assailant will come badly off; since human affairs are so variable that it is almost impossible for any one to keep an army posted in leaguer for a whole year