"We are none of us good enough for the world we have."
Israel has long had a policy called nuclear ambiguity (or opacity). It has never acknowledged that it has nuclear weapons. It is one of four nuclear-armed states that are not acknowledged as such by the Nuclear Non-Proliferation Treaty (the others are India, Pakistan, and North Korea). So, since Israel is simply continuing a long-maintained policy, which is acknowledged, at least tacitly, as a diplomatic ploy, its statement is the lesser deception. Also, Israel is not about to use its nuclear capacity to wipe another country off the map, as Iran has threatened to do with Israel. So there is hardly any moral equivalency here.
I try not to use abstractions like 'moral equivalency' or 'moral imperative,' especially when governments are involved. They are labels for judgements representing a point-of-view, i.e., one man's freedom fighter is another man's terrorist.George Bush's people used to speak of 'creating our own reality' and nuclear ambiguity sounds like that to me. Say something that isn't true and pretend it is.Israel sent one of its citizens, Mordecai Vanunu to prison for 18 years for not pretending Israel was nuclear free.
Well, in my judgment, Israel deserves to continuing existing and does not deserve to be, in the words of one Iran's spokesmen, "wiped off the map." I would therefore say that Israel has the right to pre-emptively destroy Iran's nuclear capability. Israel may have nuclear weapons, but it has not threatened to use them against anyone, including Iran. Iran may not have them yet, but their aim vis-a-vis Israel has been made plain many times overs. Si I'll take Israel's conventional fiction over Iran's existential threat.