Compared with the hopes of 10 years ago, when the Cold War came to an end, this is all rather disappointing. There was a sigh of collective relief that somehow the nuclear age had been survived and Armageddon averted as the superpowers agreed to resolve their ideological differences and become friends. Their enormous arsenals were widely dispersed, but disarmament would be a priority for the new world order.
There have been quite drastic reductions since 1990 - certainly compared with the limited arms control achieved during the Cold War. Nuclear weapons are no longer routinely deployed at sea or with armies in the field. The large strategic stockpiles have been cut back. Yet the process has been slow, and more controversial than might have been expected.
The controversy does not come from the Western side. Nato became dependent upon a nuclear strategy during the Cold War on the basis that this was the only way to deter the Warsaw Pact, with its substantial conventional superiority. Now that the Pact has disintegrated and the conventional balance has shifted decisively in Nato's favour, the West no longer needs a nuclear strategy. As Kosovo proved, its aircraft can hit almost any targets they choose (as well as some they don't) with impunity. There is a residual case for deterring other nuclear powers, and possibly other countries tempted to resort to chemical and biological warfare; but there is no need to plan to be the first to use nuclear weapons.
Unfortunately, for the very same reason, potential opponents of the West have become more interested in unconventional weapons. They know they cannot defeat the Americans and their allies in a regular battle, but suspect that they can persuade them to avoid any conflict that looks like it might go nuclear. This view has become particularly widespread in Russia. There the chaotic state of the armed forces, coupled with the growing conviction among senior officers that the US has been taking political advantage of its current strength, has led Moscow to put more, rather than less, reliance on a nuclear strategy. It is this, it believes, that will stop the Americans doing to Russia what they have just done to Serbia.
Meanwhile, Iraq and Iran have allegedly been seeking to acquire weapons of mass destruction, presumably to dissuade Washington from interfering when they throw their weight about locally. China has been rattling its missiles in its grumbling crisis with Taiwan (in which the US could easily get caught). North Korea knows that its presumed nuclear capacity is one of its few advantages in its fight for survival. Last week, India disclosed plans to deploy a substantial nuclear arsenal in the air and at sea, as tensions with Pakistan, also now nuclear, remain high.
Thus, while the spread of these weapons has not reached the epidemic proportions once feared, it has gone far enough to make nuclear disarmament much more a complex multilateral problem than a simple matter of horse- trading between two great powers.
All of this helps explain why the US Congress has been pressing for a greater investment in ballistic missile defences. This has been dubbed "son of Star Wars" in honour of Ronald Reagan's scheme of the 1980s to send satellites into space that could zap enemy missiles almost as they left their silos. This was advertised as a way to provide the US - and even its allies - with complete protection against any such attack.
Current proposals are more modest, geared to defending against rogue states armed with only a few missiles, or else an accidental launch by Russia - a real concern, as its weapons are poorly maintained by underpaid personnel with obsolete and unreliable command and control systems.
It is always difficult to argue against defensive measures, even when they are extremely expensive, and President Clinton is not trying very hard. Extra research and development expenditure has been approved, with a view to initial deployments by around 2006 - though whether it will come to anything is another matter.
The history of more than 40 years of attempts to find a way to block a ballistic missile attack is not encouraging. The problem is that the attacker has the advantage of surprise and also can employ a number of ruses to confuse the defence, such as decoys and additional warheads. The much trumpeted success of the Patriot missile in dealing with relatively short-range Scud attacks by Iraq on Israel and Saudi Arabia during the Gulf war turned out on closer examination to have been greatly exaggerated. Moreover, when dealing with nuclear missiles the margin of error is small: any successful penetration of the defensive shield spells disaster.
It was chiefly the futility of trying to defend themselves against such advantages that prompted the US and the Soviet Union to sign the 1972 ABM Treaty. Now the Americans' new plans explicitly break its provisions - which means they must either abrogate it or get the Russians to agree to amend it. From Moscow's perspective, this is all highly suspicious. Russia may be more dependent on a nuclear strategy, but its arsenal suffers from the dire state of its economy. It has no money for extensive modernisation, let alone for a ballistic missile defence of its own. Russians can envisage a situation in which they are at the mercy of the US because it can intercept their decrepit missiles before they reach their targets.
Moscow may agree to some amendment of the 1972 treaty, but it will sell its concessions hard. It wants parity with America in numbers of warheads, but this can be achieved only if the Americans agree to make substantial cuts: as things stand, their lack of resources may reduce the Russians' arsenal to a thousand warheads.
In these discussions, the Americans argue that their proposed new system is not geared to Russia but to the "rogue" states. Yet at present none of these has any missiles capable of reaching US territory. Moreover, there are other ways to deliver nuclear weapons than ballistic missiles, from so-called "suitcase bombs" to devices hidden on ships entering New York or some other port. The real missile threat from these states tends to be much more regional. Indeed, the Americans maintain that the Russians, too, have a stake in improved defences as they are definitely within range of almost all the new nuclear states. For the same reason the Americans have been working closely on "son of Star Wars" with Israel and Japan. Israel has been putting substantial resources into defensive technology after its Gulf war experience of Scuds, while Japan can see itself getting caught up in any turmoil in the Korean peninsula or Chinese aggression over Taiwan or the much disputed Spratley Islands.
Even a single warhead can do the most horrendous damage, and a country may be very grateful for an investment in missile defences if it stops just one stray or accidental missile, or deters a prospective attacker. None the less, there is a risk that such defences could create a false sense of security, easily punctured by a clever opponent. The renewed interest in these systems is a symptom of a worrying trend - the revival of nuclear threats as a short cut to political gain - but in reality they offer no solution.
Lawrence Freedman is professor of war studies at King's College London.Reuse content