Yesterday we posted about the little brother of The Bomb (strategic nuclear weapons): tactical, or lower yield, nukes. We cited a number of reasons that tactical pose as much of a threat as strategic. Among them are the exorbitant cost — modernizing the B61 tactical nukes in the U.S. stockpile will cost $10 billion. Another: they blur the distinction between nuclear and conventional weapons, as can be seen in the instance of Pakistan, which may be developing them for use against India.
On August 27, at Bulletin of the Atomic Scientists, Kingston Reif outlined issues that tactical nukes raise with extended or umbrella deterrence (stationing nuclear weapons on the soil of our allies, ostensibly to provide them with the same deterrence that Americans “enjoy”).
… the 2009 final report of the bipartisan Congressional Commission on the Strategic Posture of the United States … highlighted the importance of nonstrategic (or “tactical”) nuclear weapons. … It noted that the continued deployment of approximately 200 US nonstrategic B61 gravity bombs in Europe and the maintenance of nuclear-armed Tomahawk cruise missiles … in the Pacific are essential to extending deterrence on behalf [of] US partners in Eastern Europe and East Asia. Without these capabilities, the commission hinted, some US allies might just choose to develop their own nuclear weapons.
In other words extended deterrence, intended to protects our allies from enemies, also deters those allies from seeking nuclear weapons of their own — friendly deterrence, if you will.
As far as the United States protecting our allies, Reif concludes:
The real lifeblood of extended deterrence lies in an ally’s confidence in the strength of its political relationship with the United States. If relations fray, then extended deterrence will be perceived to be weak — no matter how many or what kinds of nuclear weapons the United States possesses.
Or, as Reif wrote in a postscript to the article at Nukes of Hazard, the blog of the Center for Arms Control and Non-Proliferation (for which he serves as Director of Nuclear Non-Proliferation):
The more US interests are intertwined with allies, the more likely the United States is to come to their defense.