Officially, the Israeli government maintains a position of "nuclear ambiguity": neither confirming nor denying its possession of nuclear weapons.  

But everyone who has studied the issue knows that this is a formula with a simple purpose: to give the United States an excuse to keep breaking its own laws, which forbid it to grant aid to a country with unauthorised weapons of mass destruction.

The fiction of ambiguity is fiercely guarded.  

In 1986, when the nuclear technician Mordechai Vanunu handed photographs of Israel's bomb factory to the Sunday Times, he was lured from Britain to Rome, drugged and kidnapped by Mossad agents, tried in secret, and sentenced to 18 years in prison.  He served 12 of them in solitary confinement and was banged up again - for six months - soon after he was released. 

Iran Didn't Spark a Middle East Nuclear Arms Race, It's Joining the One Israel Started