TM7, I only have one caveat, and it is the important one - credible threat. If I can draw your attention to the analogy again, I don't mind my neighbor having a machine gun in his yard, until he points it at my house and threatens my family.
If they have in fact stated that the purpose of developing their nukes is in order to wipe out Israel, then Israel has a problem - their neighbor has run out and bought a machine gun to shoot their kids. Are you tracking my thought? And I have read numerous original language publications, articles, periodicals, etc. that were explicitly about destruction of Israel, and not merely regime change, so you are not using the majority text threshold in your assessment.
At which case they do not lose their right to keep and bear arms as that is a God given liberty; it becomes something else entirely. And in a free world, they are liable for the consequences of their actions and their intent. If my neighbor aimed the mod2 at my kids, and articulated a threat ... clearly possessing means, motive, and opportunity ... would you say I should wait to shoot him until after my kids are dead, or can I shoot him before?
If Israel feels sufficiently threatened to carry out a preemptive strike on Iran, that's their perogative, and not ours. If the US has credible intelligence that Iran is developing their nuke capability to attack one of our carrier groups in the gulf, we are free to do whatever is in our best interest as a sovereign nation, and bear the consequences of that as well.