[153] And cities also should act upon this principle, providing in peace the things which will be necessary in time of war, and in time of war the things which will be desirable in peace, and abstaining from placing such implicit, boundless confidence in their allies, as if they could never possibly change so as to become their enemies; nor, on the other hand, exhibiting such distance towards their enemies as if they would never be able to bring them over to reconciliation and peace.