Amos Yadlin and Avner Golov of the (non-governmental) Institute for Israeli Security Studies have written an op-ed piece for the New York Times entitled "Iran's Plan B for the Bomb"
There is no evidence anywhere that Iran has a nuclear weapons program, and I defy the authors to produce such evidence. No intelligence agency in the U.S., Israel or the U.N. has ever provided any proof of this. Iran's leaders have regularly denounced nuclear weaponry and stated that it would be a violation of Islamic principles to develop one. Obviously these brute facts do not deter those who have been rooting for a military attack on Iran for decades.
The hostile-to-Iran "authorities" cited in the article have been predicting that Iran would be one or two years away from making a bomb for years. It hasn't happened.
Quite aside from the lack of evidence for any Iranian nuclear weapons program, the practical logistics in making a nuclear weapon are simply not present in Iran. The Arak plant is not on line. The claim that Iran has enough low-enriched uranium to make (the purposely vague) "several" bombs is an outright lie. The facilities for weaponizing the non-existent plutonium produced by the Arak plant do not exist, and a delivery system for a purported nuclear weapon also does not exist.
I urge all Americans who doubt what I am saying here to read the concise and accurate new book: "A Dangerous Delusion: Why the West is Wrong about Nuclear Iran" by award winning journalist Peter Oborne and Ph.D. physicist David Morrison.