Dan Drollette, Jr. in the Bulletin of the Atomic Scientists:
Although Iran’s nuclear program dominates the headlines now (and did apparently have a military dimension at one time), that program has yet to produce a nuclear weapon, judging from the available public evidence. Meanwhile, the country pushing most aggressively for complete elimination of any prospect of an Iranian bomb—Israel—has an unacknowledged nuclear arsenal of its own. Although others project higher numbers, nuclear arsenal experts Hans M. Kristensen and Robert S. Norris estimate that Israel has roughly 80 warheads, built in secret.
It is noteworthy that while negotiations over limiting Iran’s enrichment program have taken center stage in news coverage—and will likely dominate the headlines as a final agreement is or is not reached at the end of this month—the history of Israel’s covert nuclear program draws relatively little media attention. Israel has long maintained a policy of nuclear ambiguity, neither confirming nor directly denying that it has a nuclear deterrent, and the United States government has officially taken the same stance, prohibiting its officials from stating that Israel is a nuclear weapons country.
More here.