Both essentially contend that we should leave Washington alone to determine the nuclear forces it needs in order to continue doing what it has done so successfully for more than 60 years. The trouble is that there is a significant body of opinion in the U.S. (including President Obama) that believes business as usual in the strategic nuclear arena may no longer be the smart choice. Obama has acknowledged that the U.S. may have no choice but to continue business as usual but he seems to want to shake the tree and see if a different road emerges as viable.

This apparent change in the balance of opinion in Washington will become more clear when either the new U.S.-Russia strategic arms reduction treaty or the nuclear test ban treaty goes to the Senate for ratification. The apparent change has nothing to do with the Australia-Japan commission — but the report addresses issues that the U.S. is beginning to look at from a fresh perspective.

The two biggest factors behind the shift in the U.S. are, first, that the circumstances (and the imaginable contingencies) in which robust nuclear deterrent capabilities seemed so indispensible and effective are declining in prominence while the growing challenges (notably, of course, terrorism) seem relatively immune to the restraint and discipline that nuclear deterrence can help to foster. The second factor has been (belated) acceptance that continuing to indulge the instinct that peerless nuclear capabilities are of irreducible importance will almost certainly mean a continuous trickle of new nuclear weapon states and that this will compound the difficulty of sustaining the non-use of nuclear weapons.

The international community’s determination to put resistance to the proliferation of nuclear weapons ahead of other interests has never been unqualified. But it has weakened since the end of the Cold War. And a key part of the explanation is widely considered to be perceptions that nuclear powers have been reluctant to live up to promises to negotiate in good faith toward nuclear disarmament.

Nuclear disarmament, in my view, is unimaginable from our vantage point. There are hugely difficult and interdependent issues that have to be resolved or transformed before the process of nuclear diminution can be expected to proceed to the next stage. The Australia-Japan commission wisely stopped short of advocating relentless progress to zero in favor of imaging a new plateau at 5-10 per cent of the number of nuclear weapons estimated to exist. From such a vantage point, one could think more credibly about what complete abolition might involve. In arriving at this recommendation the Commission worked through many ideas on how the major nuclear states can signal their commitment to de-legitimising nuclear weapons and building a foundation that will support minimal nuclear forces performing limited functions. The Commission recommends that the nuclear weapon states seek to confine the role of nuclear weapons to deterring their use by others, to adopt unequivocal declaratory policies of “no first use,” and to work toward operational arrangements that make these weapons slow to react rather than on high alert and available at a moment’s notice.

The Commission report places primary responsibility for transformative change on the United States. This is appropriate: the U.S. has asked the most of, or leaned more heavily on, nuclear deterrence than any other state. Significantly, however, the report stresses the importance of early and sustained substantive support from other nuclear weapon states Whatever consensus emerges in the U.S. to explore new thinking on the bomb can readily be crushed by the contention that other states are holding back in the hope of securing some advantage. Deciding what can reasonably be expected of other states, finding creative ways for them to meet these expectations, and remaining resolute in requiring that they do so will be an important responsibility for all states but especially, perhaps, for America’s allies and friends.

To regard nuclear disarmament as unimaginable is not the counsel of despair. Nuclear deterrence is an art, not a science. Strategic nuclear deterrence has relied on the sensation that crossing the nuclear threshold would take states into an abyss where logic, strategy, tactics, winning, and losing become irrelevant. This sensation inclines states to not even begin to go down paths that might lead to someone thinking about nuclear use. When observers say that nuclear weapons are uniquely effective in generating deterrence they are referring to things that may well have led to confrontation and the risk of war but did not and would not because the Bomb sat at the end of the road.

But how many nuclear weapons equal an abyss? Insider accounts of nuclear crises – the biggest one being the Cuban crisis in October 1962 – suggest that political actors regard the risk of a single nuclear detonation on their soil as utterly compelling. So there is a lot of scope to play with numbers. We might also ask whether we should, as a community of states, be content to live with the threat of a nuclear abyss as the only reliable means of ensuring that states behave responsibly.

Hard-headed realists in Australia, and in the other 30-odd countries that ‘consume’ U.S. assurances of extended nuclear deterrence may counsel gravely that Washington should not and could not do other than to stay with what seems to have worked for so long. But the U.S. may be getting to a point where the balance of its interests will incline it to invite its allies and friends to think hard about how to get along with a U.S. nuclear arsenal that looks and feels very different, both in absolute terms and relative to those of Russia and China. That, it seems to me, is the real issue.

This piece was first published by Pacific Forum CSIS in PacNet Newsletter #3, 2010.

Ron Huisken is Senior Fellow, Strategic & Defence Studies Centre at the Australian National University.