In thinking about deterrence-based national security, Israel must regard the country's nuclear and conventional threats as seamless and interwoven. This is because a recognizably capable and coherent conventional deterrent could prevent any too-sudden escalations to nuclear dimensions of conflict, and because a similarly capable and coherent nuclear deterrent could best ensure that adversaries remain suitably reluctant to menace Israel's existence. Moreover, because both interrelated forms of Israeli deterrence always require a presumption of enemy rationality – and because these enemies might not always conform to this reassuring presumption – Israel will have to develop a far more conspicuous doctrine for dealing with prospectively non-rational adversaries. While any such doctrine, inter alia, must include a broad variety of plausible preemption choices, there are conceivable circumstances wherein Israel's pertinent enemies would be judged irrational or potentially irrational, and where identifiable cost-effective preemption options no longer exist. At that eleventh-hour point of crisis, Israel's leaders would need to have ready certain still-promising security options other than deterrence (conventional or nuclear) or preemption.