It is a commonplace that the history of civilization is largely the history of weapons.  In particular, the connexion between the discovery of gunpowder and the overthrow of feudalism by the bourgeoisie has been pointed out over and over again.  And though I have no doubt exceptions can be brought forward, I think the following rule would be found generally true: the ages in which the dominant weapon is expensive or difficult to make will tend to be ages of despotism, whereas when the dominant weapon is cheap and simple, the common people have a chance.  Thus, for example, tanks, battleships and bombing planes are inherently tyrannical weapons, while rifles muskets, long bows and hand-grenades are inherently democratic weapons.