Writing in the Jerusalem Post, Louis Rene Beres makes a thought-provoking argument that, for the sake of improving its deterrent effect against Iran, the time is near for Israel to make public its nuclear weapons program:

To be deterred, a fully nuclear Iran would need to know that Israel’s nuclear weapons are both invulnerable and capable of penetrating its defenses. Any Iranian judgment about Israel’s willingness to retaliate with nuclear weapons would depend in part on a foreknowledge of these weapons.

Any Iranian belief that Israel’s nuclear weapons are exclusively mega-destructive must be modified. The enemy must be convinced that the Jewish state possesses a range of weapons to meet a range of threats, so the credibility of a deterrent posture could vary inversely with the perceived destructiveness of Israeli arms.

Presumably, he means that Israel ought to divulge the extent to which it possesses MIRVs, tactical nukes, anti-missile warheads, nuclear-capable submarines, and nuclear-hardened silos.  Although Beres assumes that neither Israel nor America will take preventive action against Iran (a subject David Kay recently and helpfully discussed), it seems perfectly possible to combine his suggested sunshine policy with one of keeping all military options open.