[Abraham]

In general, a bit of responsability and moderation comes with the job of Prime Minister (or President, in nations with the Presidential system).
Avigdor Lieberman is in my view a lunatic, infected by the same virus that earlier created Hezbollah and Hamas.
However, Lieberman is not much more than democratic proof that there is a faction of fanatics in Israel too. He'll never lead the country, because the people of Israel are - given the circumstances - on average moderate and very democratic minded.

I consider the case of Ahmadinejad far more serious.
Iran is by no means a real democracy, but far closer to a dictatorial theocracy. 'Herr' Ahmadinejad openly speaks of "wiping Israel off the face of the earth" and he or his successor might in a couple of years have the means to make his sick dream come true.
What would stop him?
A supervising fundamentalistic Shi'ite council?
A sudden streak of humanism or moderation?
An Act of God?
Decisive diplomatic action from the West and/or the major world powers? Decisive military action from the West?
From the U.S.?
From Israel?
Keep sitting on your hands hardly seems an option for the world, especially for Israel and the U.S., unless the lessons taught 70 years ago by that other 'Herr' are forgotten...

By the way, I don't see any advocacy for 'Muslim Nuking' in this thread.