With the political corruption stories sprouting mushroom-like all over the place, it's worth going to the Chumpchanger backlist for a well considered and still startlingly relevant take from someone in a position to know a lot about the temptations of public office. From Francis Bacon's essay Of Great Office:

Men in great place are thrice servants: servants of the sovereign or state; servants of fame; and servants of business. So as they have no freedom; neither in their persons, nor in their actions, nor in their times. It is a strange desire, to seek power and to lose liberty: or to seek power over others, and to lose power over a man's self. The rising unto place is laborious; and by pains, men come to greater pains; and it is sometimes base; and by indignities, men come to dignities. The standing is slippery, and the regress is either a downfall, or at least an eclipse, which is a melancholy thing. ... Certainly great persons had need to borrow other men's opinions, to think themselves happy; for if they judge by their own feeling, they cannot find it.

Bacon served as attorney general and later Lord Chancellor of Great Britain under James I--a post he lost in an embezzlement scandal.