For assorted reasons, none of which might make any sense in retrospect, neither Israel nor the United States has yet exercised an appropriate pre-emption option in Iran. In essence, such a self-defense option would have been directed against certain pertinent Iranian nuclear assets and infrastructures. At this point, at least for plainly operational reasons, launching pre-emptive strikes of this sort may have become too costly. This is because the expected retaliatory consequences of any Iranian reprisal, although nonnuclear, could now be unacceptable.
Pre-emption in this critical security matter has never really been a legal issue. International law, after all, is not a suicide pact. Israel has never been under any obligation to sit back and depend upon "sanctions." Always, especially in the face of openly genocidal threats from Tehran, it has had a right to undertake "anticipatory self-defense."
Left unchallenged, by Israel and by the United States, Iranian nuclear materials could sometime be shared with various Iranian surrogate groups, including Hezbollah, or other jihadist organizations. In turn, these well-organized and highly motivated terrorist groups could then threaten the American homeland using cars, trucks or ships as delivery vehicles.
More than likely, however, Israel will soon have little residual choice but to learn to "live with" a nuclear Iran. More precisely, this will mean an obligation to forge a complex and durably focused posture of nuclear deterrence. Any such posture, of course, would be backed up by a very capable program of active defense.
If Israel's ballistic-missile defense (BMD) systems were somehow maximally efficient, even an irrational Iranian adversary armed with nuclear and/or biological weapons could still be controllable. Here, even if Israel's nuclear deterrent were immobilized by an enemy state that was willing to risk a massive "counter-value" Israeli reprisal, that aggressor's first strike aggression could still be blocked by Arrow. But these required missile interception-capabilities are simply not plausible.
To deal with the continuing Iranian nuclear threat, since President Obama's recent rapprochement with Iran's new president, Hasan Rouhani, hasn't really changed anything, Israeli planners shouldn't assume enemy irrationality across the board. Although such irrationality could remain a distinct possibility, it is by no means the only cause for ongoing strategic concern in Jerusalem, Tel-Aviv and Washington.
Even a fully rational nuclear Iran could represent a significant, and potentially existential, threat. This is because a rational adversary could still be subject to misinformation, miscalculation, unauthorized firings, cyber-distortions, and various related forms of electronic, mechanical or computer malfunction.
Today, any once-remaining American willingness to pre-empt against Iran has likely disappeared. Now, it is essentially unimaginable that an American president would still resort to any such expression of U.S. military force. Israel, it follows, must immediately take certain far-reaching steps to strengthen and sustain its national nuclear-deterrence posture.
To be deterred by Israel, any rational adversary, including Iran, would always need to calculate that the Jewish state's second-strike forces were sufficiently invulnerable to first-strike attacks. Facing Israel's Arrow interceptor missile, this adversary would require more and more missiles to achieve what it would consider an assuredly destructive first strike capability against Israel. This is why the Arrow could compel a rational enemy to delay or even discard any contemplated first strike attack against Israel.
Israel must continue to develop, test and implement an active defense interception capability to best match the growing threat dictated by Iranian nuclearization. It must also take appropriate steps to assure relevant decision-makers in Tehran that Israel's nuclear weapons are usable, survivable and penetration-capable. For this to work properly, Jerusalem will have to consider, among other measures, taking its bomb out of the "basement."
Soon, Israel will need to shift away from its long-standing policy of deliberate nuclear ambiguity, and toward a discernibly new policy of selective and partial nuclear disclosure. While this shift would not be greeted with approval in Washington, or in any other national capital, it would still support Israel's core security interests.
In the best of all possible worlds, Iran would never have been allowed to proceed toward a full nuclear-weapons program. But this is not the best of all possible worlds, and the next feasible steps for Israel, the state most directly threatened by Iranian nuclearization, will need to involve a substantially enhanced strategy of national nuclear deterrence.
Louis Rene Beres is a professor of political science and international law at Purdue University and the author of many books and articles dealing with nuclear strategy and nuclear war. Retired Lt. Gen. Thomas McInerney, the co-author (with Maj. Gen. Paul E. Vallely) of "The Endgame: The Bueprint for Victory in the War on Terror" (Regnery) is a Fox News military analyst.