So what sources is Netanyahu relying on, if not his own international spy agency? As Mossad's estimates coincided largely with Washington's, it appears he was not even receiving conflicting briefings from the Americans.
Also, unlike Netanyahu's claim at the UN, the Mossad document did not suggest Tehran was trying to build a bomb. It stated that Iran's efforts to develop what Tehran claims is a civilian nuclear program would give it a technological capacity that could be redirected at short notice towards a military program.
But that is true by definition. Advances in any state's development of nuclear technology -- even if only for peaceful purposes -- help move it closer to a situation where it could choose to make a bomb.
The speed of enrichment then becomes the nearest thing to an objective yardstick for interpreting Iran's behavior. And Mossad viewed Iran's enrichment rate as no cause for concern.
Vicious feud
More significantly, however, the document provides the context for understanding a vicious feud that has been brewing between Netanyahu and his spy chiefs for at least the past four years.
Unable to speak out directly themselves, serving spies have instead been using as mouthpieces the departing heads of Israel's leading security agencies.
The most significant has been Meir Dagan, who has been battling Netanyahu in public since he stepped down as Mossad chief in December 2010, more than a year and a half before the leaked report was published.
In January 2011, a month after leaving Mossad, Dagan called Netanyahu's hints that he wanted to attack Iran the "stupidest thing I've ever heard." Ephraim Halevy, a predecessor of Dagan's, also cautioned that Iran did not pose an existential threat as Netanyahu claimed, and that an attack could wreck the "entire region for 100 years."
Yuval Diskin, who quit the Shin Bet domestic intelligence service in 2011, also joined the fray. A few months before the prime minister's UN speech, he accused Netanyahu and his defense minister Ehud Barak, who was also said to support an attack, of being "messianic."
He added: "These are not people who I would want to have holding the wheel in such an event. They are misleading the public on the Iran issue."
Netanyahu's judgment in critical situations was also called into question by an article in the Haaretz newspaper in summer 2012, shortly before his address at the UN.
In February 1998, wrote Haaretz, Netanyahu had ordered for the first time in Israel's history the use of nuclear weapons -- against Saddam Hussein's Iraq after it launched missiles at Israel in retaliation for the West's punitive sanctions and no-fly zone. The order was rescinded, according to Haaretz, only after three generals talked him out of it.
The incident was apparently well known to Israeli military correspondents at the time and one, Zeev Shiff, wrote an article urging what he called a "Red Button Law" that would prevent a prime minister from ever having such unilateral power again.
Black arts
Nonetheless, given the black arts of all intelligence services, it was possible that the image of an emotional and unstable Netanyahu may not have been entirely reliable.
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