IN the Pentagon they are sometimes referred to, ominously, as ``the undeterrables.'' They are considered unpredictable, a bit unstable - and the No. 1 nuclear danger to the United States in the post-cold-war era.
They are the rogues of the world, both nations and terrorists. North Korea is one, Iraq another, the Islamic (Palestinian) Resistance Movement (Hamas) a third. Some have clandestine atomic weapons programs of their own. Others are thought to be shopping for a loose nuke from the ex-Soviet Union's huge arsenal.
As the Pentagon undertakes its most sweeping review of United States nuclear weapons strategy in 45 years, defense officials say the so-called ``undeterrables'' are the most important problem they will address. Are they, in fact, untouchably intent on their aims? Or can the US nuclear arsenal of multiple-warhead missiles and billion-dollar submarines, built up over decades of cold-war standoff, be reoriented to deter renegade groups as it (apparently) did the Soviet Union?
In the long nuclear competition with the Kremlin, the US established a kind of comfort level, noted Secretary of Defense Les Aspin when announcing the nuclear review last week. Both sides could easily identify where danger lay. Both sides counted on the other fellow being rational.
Today, with smaller adversaries completely different from the old USSR, ``we can't count on either of those assumptions,'' Mr. Aspin said. In the past, US nuclear weapons were ``the big equalizer,'' he noted. The destructive threat of atomic attack was enough to balance out any perceived advantage of the Soviet bloc in conventional weaponry.
In the post-cold-war world, it is the US that has had the biggest conventional stick on the block. Yet if a potential adversary - say, Saddam Hussein - had even a few nuclear weapons, the US advantage in M-1 tanks and Cobra attack helicopters might go for naught. US forces could be `equalized'
``We could turn out to be the equalizee,'' ruefully noted Aspin in a candid moment. That could very well be what US officials are worried about with North Korea. A nuclear-armed Pyongyang could force a number of strategic changes in Asia, including a possible Japanese nuclear program, that the US would dislike, yet be unable to stop.
President Clinton reiterated over the weekend that North Korea ``cannot'' be allowed to develop the bomb. But quiet carrot-and-stick diplomacy has not to this point appeared to dissuade North Korea's leaders from their apparent aims.
Whether stronger measures such as economic sanctions would work is problematic, given North Korea's almost-paranoid isolation from the world.
In recent days, US commanders have been warning that North Korea's response to increased pressure could be a conventional attack on the south. If that happens, South Korean forces and the 37,000 US troops based in Korea might be hard pressed to stem the tide, claims a former Pentagon Joint Staff analyst of the region.
``Our options are very limited for North Korea,'' says Bob Gaskin, now an analyst at Business Executives for National Security.
The nuclear doctrine of the US, of course, would be only one aspect of dealing with North Korea or other unpredictable states. Other levers of geopolitical influence would be pulled as well. Magnitude of threat much less
And while a nuclear-armed North Korea would be a great menace, the physical nuclear threat to the United States is now an order of magnitude different than it was in past decades, note defense officials.
No longer are US cities the object of a Soviet arsenal, which peaked at over 12,000 warheads in the 1980s. Yet as arms control agreements promise to bring the US arsenal down to some 3,500 warheads, targeting is still governed by official ``presidential guidance'' signed during the cold-war years.
The Defense Department plans to finish its comprehensive nuclear review by spring, with the aim of producing new presidential guidance. The review consists of groups addressing six topics: the role of nuclear weapons; nuclear-force structure; nuclear-force operations; counterproliferation efforts; weapon safety; and the forces of the former Soviet Union.
Among the big questions to be studied are whether US forces should more directly threaten rogue states. Some analysts, for instance, take the politically controversial stance that the US needs a new, smaller nuclear weapon that would be a more credible threat to rogue nations.
Some officials also say the US should not rule out retaliation with nuclear weapons for an attack with chemical or biological weapons - possibly another controversial point in the study. Some analysts say this stance would encourage proliferation.