I have seen a lot of dictators interviewed on film or TV. This specimen falls into the category of the charismatic megalomaniac. (And this was through a translator; in Farsi I'm sure he's another Jon Stewart.) Had Hitler been alive during the TV era, he would have been as effective, appealing and scary. Ahmadinejad is smart, funny, evasive and a consummate liar, much like the late, lamented Saddam Hussein. (And Stalin and Mao and Castro and Ho and for all I know Pol Pot.)
He is a profoundly dangerous person. The West is fundamentally ill-equpipped to deal with such a personality (just as we were at Munich in 1938 and Yalta in 1945). The West is all about reason, negotiation, and the measured application of leverage (“Doesn’t everyone want peace?”).
Like Hitler, Ahmadinejad is serious and rational. He believes that it is his holy duty to advance the cause of Shi’a Islam and to eliminate, in the name of God, the “Zionist Entity”, which both Hitler and he would agree on, for different reasons.
WW2 was about the “have not” powers versus the “have” powers. That is precisely what is happening today with the “other” powers: Russia, China, and Iran. Except that Russia and China ultimately do want peace and prosperity, on their own terms, while Iran places no value on peace (Jihad is a commandment). It seeks to pursue Islamic goals by nuclear means.
Ahmadinejad is no Brezhnev. Peaceful coexistence is not his goal. If he destroys Israel, he goes to heaven.
How do you deal with a serious, rational, fanatical enemy? I don’t know, but it would be wrong to think that you can "negotiate" with a fanatic.