Thucydides......................

Then there is the matter of Thucydides himself.  Greece's preeminent historian was not merely an analytical and systematic writer of a great extant military history of Sparta and Athens.  He was also a brilliant philosopher who tried to impart to the often obscure events of the war a value that transcended his age.  In his own boast, his narrative would prove to be "a possession for all time,"  far more important than the war itself.
     Precisely because of this didactic nature of Thucydides' lengthy narrative - predicated on the belief that human nature is unchanging across time and space and thus predictable - the conflict of Athens and Sparta is supposed to serve as a lesson for what can happen to any people in any war in any age.  A central theme is the use and abuse of power, and how it lurks behind men's professions of idealism and purported ideology.  What men say, the speeches diplomats give, the reasons states go to war, all this "in word" (logos) is as likely to cloak rather than to elucidate what they will do "in deed" (ergon).  Thucydides teaches us to embrace skepticism, expecting us to look to national self-interest, not publicized grievances, when wars of our own age inevitably break out.

-Victor Davis Hanson,  A War Like No Other