For other such spectacular script changes, look at how the roles of Russia and China as "friend, ally, and trading partner" or "Godless Communist enemy of humanity" have been altered repeatedly since 1925! ;-) Why be surprised that Iran's script has totally reversed itself since 1925? It would be more surprising had it not. Official "friends" become official "enemies" the moment they have something you want and won't surrender it...or the moment they stand in the way of your next grand plan.

It's all a matter of self-interest and imperial expediency. The Empire has designs on Iran at this time. Iran is no threat to the Empire and very little threat to Israel, but the Empire is an absolutely deadly threat to Iran.