Iran doesn't directly threaten the existence of Israel either.

I expect that all of this hand wringing about Iran is a part of the attempt of certain people to try to ensure that Ahmadinejad wins the election this time. Heaven forbid that they wouldn't have him as their excuse to attack Iran any more. Even if he loses, they will still try to make the case that Iran should be attacked because of the Iranian regime's human rights violations. The people who make that argument are doing so in spite of the fact that the People of Iran do not want such interference in their country, regardless of the behavior of the Iranian government. They want to be left alone to fix their problems themselves.

And once again, Iran has not directly threatened the existence of Israel.