millennia, differing according to whether their primary political units were city-states,
empires or nations, but different ‘[i]nternational-political systems, like economic markets,
are individualist in origin, spontaneously generated, and unintentional’.3
Thus, not
only is history not necessary, given that the fundamental nature of international life has
changed little over ‘millennia’; it would in any case be difficult to construct an intelligible
account of historical change in the international arena. For Waltz, as for many other
realists and neo-realists, reasoning: