The emperor has no clothes. The threat of massive nuclear attack which has long covered the rationale for the extensive (and expensive) US nuclear weapons program has been reduced to a small scarf, covering barely anything.
Defense is the first requirement of a government - if it fails, all other programs become moot. But it has been two centuries since the United States has been threatened by invasion or occupation. During World War I and then World War II, there was a threat of Eurasian domination by Germany, then together with Japan, and an implied threat of some kind of subsequent hostile global domination. The Cold War continued this threat, while the rise of extensive nuclear arsenals brought a new threat, for the first time in over a century, of destruction of the nation. Defense against this threat was inadequate, forcing the nation to rely on deterrence.
Deterrence depends on an opponent's rationality and is inherently uncertain. It is compounded by a very awkward and inconvenient fact: any sovereign nation has as much inherent right as the United States to develop its own nuclear weapons program. Most nations, by signing the Nuclear Nonproliferation Treaty, have voluntarily agreed not to do this, partly in exchange for an agreement by the nuclear weapons powers to eliminate their own arsenals. North Korea withdrew from the treaty, though not fully in compliance with its provisions. Regardless of the despotic character of its regime, its development of nuclear weapons in the face of an obvious threat of US use of force can only be evaluated as rational. Iran's apparent development of a nuclear weapons capability underlines the difficulty of stopping a determined nation from developing its own program; concerted and coordinated international pressure is required and can be very difficult to achieve.
Pseudorational analyses of deterrence requirements during the Cold War led to totally irrational force levels on both sides as calculations of counterforce strikes, launch on warning options, residual force capabilities, and required levels of destruction became more and more arcane. With a gradual recognition of the background threat of Nuclear Winter, the irrationality of Mutually Assured Destruction (MAD) became incontrovertible and led, even during the height of the Cold War, to arms reduction agreements. With the demise of the Soviet Union and subsequent development of broad relations between the West and Russia, this threat has all but disappeared.
Even without any retaliatory strike, the threat of Nuclear Winter makes a massive Russian nuclear strike on the United States totally unattractive. And retaliation would certainly follow, probably harsh and blunt, an eye for an eye, a city for a city, a nation for a nation. Perhaps it would be more discriminatory, even nonnuclear so as not to compound the global challenge of Nuclear Winter. Regardless of the exact US response, Russia would also suffer a devastating blow. It is hard to imagine circumstances which would bring the Russian leadership to launch such a strike on the United States. And if it did, a comparatively small nuclear force could be sufficient for retaliation.
The biggest deterrent is the growth of broad political, diplomatic and social ties between Russia and the West. The case of France and Germany is instructive. These two historical enemies sit aside one another, with France being nuclear armed. But there is no pressure in Germany for it to develop its own nuclear deterrent. War between France and Germany is now unthinkable and deterrence is irrelevant. The only significant threat remaining from Russia is that the nation would somehow deteriorate into a paranoid dictatorship, reversing two decades of both internal and external development. The biggest requirement for bolstering deterrence with Russia is thus not improving the US nuclear posture but rather promoting the continuing development of a prosperous and democratic Russia.
China poses the only other threat of massive nuclear attack, and it is a potential future threat. China now maintains a minimal deterrent and is wholly incapable of launching a comprehensive nuclear strike. It shows no inclination to engage in any sort of major nuclear buildup or some kind of nuclear arms race with the United States. Relations between the two countries would have to deteriorate massively for such an eventuality to take place. So, as with Russia, it is decidedly in the US interest to promote the development of a secure and prosperous China and the evolution of a more open and democratic leadership.
India and Pakistan present a troublesome situation; they represent the highest global risk of actual nuclear war. But it is hard to imagine circumstances in which US nuclear forces would become involved. And even if, somehow, this were the case, there is no prospect of a need for more than a few weapons. It would be more complicated if China were somehow drawn into the fray, but even then the United States would be more of a bystander and neutral negotiator.
A nuclear-armed Iran would be another troublesome situation. It would not pose a direct threat to the United States, but some threat to regional allies in Europe which depend on a US nuclear umbrella. Nevertheless, Europe seems basically little concerned about this possibility, so US nuclear requirements here, if any, are also small. Iran has voiced threats to Israel, but in extremis Israel seems capable of providing a retaliatory response on its own. US nuclear requirements here are also minimal.
North Korea presents the only other state challenge. Its weapons could certainly devastate Seoul or Japan, and potentially even pose some threat to Hawaii. Any North Korean nuclear strike would certainly provoke a massive retaliatory effort and end the current regime. US nuclear requirements would again be modest, indeed, it would make little sense to incinerate Pyongyang or other major North Korean cities. More importantly, US nuclear weapons may be irrelevant. Any actual use of nuclear weapons by the North Koreans would be suicidal. The most prominent scenario would be if the leadership were facing collapse and decided if they were going down, then everyone would go down, and directed the launch of whatever weapons they could in a final paroxysm of destruction.
The final nuclear threat is a terrorist threat. Against this, US retaliatory capabilities and nuclear capabilities are irrelevant. The most important requirement is the one focused on during the recent nuclear security summit, preventing the spread of nuclear technology.
Overall, the maintenance of large US nuclear forces undermines this objective, even though strategic nuclear forces have limited utility.
- Larger US forces inevitably mean larger forces globally. The larger that forces are, the more potential for accidents, rogue operations, or insider incidents. Nuclear weapons security programs now depend heavily on computer operations, and hackers have shown unequivocally how inadequate these can be. Disgruntled insiders in any of the nuclear weapon states could initiate a disastrous chain of events.
- Maintaining large nuclear forces as a base of national power only encourages other nations to do the same. So, for example, if Iran succeeds in developing its own nuclear weapons, there will be significant pressure on other regional states to develop their own.
- Weapon arsenals invite responses by potential opponents. Likewise, weapons reductions can promote weapon reductions by other. In fact, there have been recent proposals for Britain and France to combine nuclear efforts, reducing their overall levels.
There has been much discussion on weapons modernization and the need to maintain high levels of reliability. This is mostly a red herring. While it is true that maintaining weapons on the shelf for decades will result in some level of deterioration, this is true for all the nuclear weapon states. With its extensive non-nuclear testing, years of data from prior nuclear tests, and advanced computer simulations, the United States is probably able to maintain its weapons at a higher stage of readiness than any other nation. In fact, high reliability is more important for a state considering a first strike than for the United States focusing on deterrence, so a gradual deterioration of nuclear weapons worldwide actually favors the United States by reducing the attractiveness of a first-strike option.
Tactical nuclear weapons are also an important consideration, mainly in Europe. At one point, the United States relied on them as a counterbalance to superior Warsaw Pact forces, but that time is long past. Continued Russian deployments of tactical nuclear weapons could potentially be used to intimidate European nations which seem little disposed to counter this theoretical threat with other nuclear weapons. Continued broadening of EU-Russian relations seems the surest route to diminishing and then eliminating these weapons. At any rate, it is hard to see how US strategic nuclear weapons play a role in this arena, although theater weapons can offer options potentially important in a nuclear crisis.
Overall, deterrence is a fragile tool. It is inherently incapable of providing high levels of assurance. The nuclear weapons element of a deterrence posture can be superficially reassuring as it can be quantified and evaluated with some degree of assurance. It does provide the retaliatory potential that discourages any first strike by potential opponent, but it also increases the potential for insider problems and diminishes nonproliferation norms. No matter what you do, you can not prove deterrence. The most significant elements of deterrence are not nuclear weapon postures, but broad relations between competitive powers, and these are not quantifiable. Ironically, efforts to improve the quantitative aspects of deterrence can undermine the nonquantative aspects by encouraging potential opponents to increase their own capabilities. This was what led to the Cold War MAD impasse and a chillingly close call with the Cuban Missile Crisis. In the final analysis, it is the nonquantifiable aspects which are the most important.
The other unfortunate element of a strong nuclear posture is cost. This approach would make more sense if the United States had large available resources to put to this use. Unfortunately, the US internal situation is also very bothersome and military expenses, including oversized nuclear forces, undermine long-term security. The economy remains burdened and new health care benefits will further increase deficits. Although some economic indicators have improved significantly, unemployment in particular remains high and future jobs remain problematical. The nation continues to drift toward a bifurcated society, while widespread financial pressures promote increasingly polarized politics and alienated, violent individuals. The budget crisis at the state level is badly exacerbating the already poor showing of US education, undermining the potential for continued economic dominance. US infrastructure continues to deteriorate, disaster preparations are still fragmented, and the US incarceration rate remains the highest rate in the world. On top of all that, immigration is still is vexing problem, with the United States serving as an economic safety valve for Mexico and much of Central and South America, even though jobs are more and more difficult to find.
This leaves the United States unprepared to respond dynamically to looming global crises in resources, particularly energy, but also water and food worsened by rising population levels, bitter regional confrontations, and inexorably worsening global warming. Avoiding global turmoil is the most pressing strategic challenge of the XXI Century. The United States needs every penny it can get to put to positive, productive uses, creating a new economy based on prosperity without growth, while promoting hemispheric development to reduce immigration pressures and global prosperity to address the challenge of widespread turmoil. If it cannot meet these socio-economic challenges both domestically and globally, it will unable to maintain its own prosperity and social cohesion and will inevitably decline as a global power.